DE69915370T2 - ANTENNA SYSTEM FOR IDENTIFICATION WITH RADIO FREQUENCIES - Google Patents

Description

AREA OF INVENTION

embodiments The present invention relates to communication systems of the type with several transmitting and receiving devices, which is a common Sharing communication medium, and method for establishing communication in the presence of large ones Numbers of such devices.

BACKGROUND THE INVENTION

conventional Data communication systems have been used to provide object identification Use of the broadcasting medium. Such radio frequency identification (Radio Frequency Identification (RFID) systems are used in the fields the conveyor technology, Warehouse management and generally in the field of tracing Staff, objects and animals used. In an exemplary arrangement, a such an interrogator system and several thousand transceivers Include each transceiver as a disposable label or trailer packed and on an object to be tracked, animal or one Person is placed. Each transceiver is using IC (Integrated Circuit) technology produced, with a unique Identifier programmed and mounted with a microstrip antenna, to a flat structure for installation in the label or the trailer too form. Typically, the interrogator has a fixed one Place on while Transceivers from time to time in the communication area of the interrogator be moved in and out there. It is highly desirable transceivers from a set of transceivers that can count millions, exactly and to identify quickly.

simultaneously It is highly desirable that Reduce the cost of each transceiver to an absolute minimum.

A accurate and reliable Detection of transceivers is complicated by a number of factors which include, for example, that (a) Transceivers have a limited amount of energy required for operation available is if with a radio transmission must be answered; (b) the orientation of the transceiver antenna for absorbing sufficient energy from that sent by the interrogator Signal may be inappropriate; (c) the orientation of the antenna of the Transceivers to deliver one for one accurate reception by the interrogator sufficient transmission signal may be inappropriate; (d) the interaction of a transceiver with the interrogator require sophisticated logic in the transceiver can be the part of a communication protocol of the transceiver to carry out exactly that is used to provide an open communication channel between the interrogator and a single transceiver; and (e) transceivers transmitting simultaneously a so-called collision cause.

It There is a need for a communication system for coordination the use of a common medium among potentially millions of transceivers for query or for control activities that are in a limited time are, is suitable. additionally There is a need for some applications with every transceiver required complexity the circuit, firmware and software minimize to the communication workspace to expand and larger numbers of individual identification numbers probably at the expense the complexity to support the interrogator. Without these improvements can the size and cost Pro transceivers will not be reduced to new and improved communication systems to allow the cost-effective disposable transceivers, such as identification tags, luggage tags, inventory tags and the like.

SUMMARY THE INVENTION

The invention is directed to an antenna network for operation with a provided controller, wherein the controller provides a first signal for transmission through the network, responds to a second signal provided by the network in accordance with receipt by the network, and a plurality of binary coded ones Providing commands to the network, the network having a plurality of antenna nodes, wherein: a) each node is coupled to the controller for receiving a respective command of the plurality; and b) each node comprises: (1) a plurality of transceiver channels, each channel comprising: (a) a transmit circuit for transmitting in response to the first signal; (b) a squelch; and (c) a receiving circuit, wherein the second signal is selectively provided in response to an output signal of the receiving circuit; and (2) coupling means for selectively coupling a particular transceiver channel of the plurality to any one of a plurality of provided antennas in accordance tion with the respective command.

One The system relating to the present invention includes a monitoring device and a variety of transceivers that share a common medium communicate. The monitoring device contains a first transmitter, a first receiver and a processor. Each transceiver contains a resonant circuit, one Transmitter, a receiver and an antenna coupled to the resonant circuit. The processor introduces Method of implementation of transceiver communication, which includes the steps of: (a) transmitting from the first transmitter a first frequency for a first period of time; (B) after elapse of the first period of time, receiving a response signal at least one of the oscillating circuits via the first receiver; (C) Determining a second frequency from the received response signal; and (d) perform of transceiver communication using the second frequency.

Transceivers of the type with a resonant circuit coupled to an antenna, if they are close to each other in operation, the answer of a single Transceiver by absorbing the to be received by the transceiver provided energy, absorbing the sent from the transceiver Energy or by changing disturb the resonant frequency of the resonant circuit. By determining the second Frequency for the transceiver communication may be used by the monitoring device Establish communication with the individual transceiver on a frequency the one to transfer from power to the transceiver, to keep a query log to identify the transceiver or better for data transfer is. The communication becomes despite variation of the resonance frequency maintained the resonant circuit, which discussed above with reference to Coupling or by variation of the manufacturing and operating environment (z. Temperature, humidity, relative movement or aging of components) can result.

The monitoring device can also a first antenna coupled to the first transmitter and a squelch to the dissipation of energy at the antenna after the lapse of the first time period and before receipt of the response signal from the resonant circuit from the first receiver contain. By fast energy dissipation, the response signal from the second receiver can be received faster and more accurately and, consequently, the second Frequency can be determined faster and more accurate, what the system sensitivity and reliability elevated. To achieve a faster reception from the second receiver expands the working area of the monitoring device or leave one Operation with weaker ones Signals too. weaker Signals can established in transceivers be different from the monitoring device further away or in an orientation that is responsible for the reception through the first receiver is disadvantageous. Such a disadvantageous orientation of the antenna in the transceiver can with respect to the first antenna of the monitoring device or with respect to other transceivers in the vicinity of the transceiver antenna.

The monitoring device can also a second receiver, the for provides a phase detection, or contain a signal analyzer, the for provides a phase detection. Phase detection provides phase information in terms of the received response signal. The processor can Furthermore determine the second frequency according to the phase information. The phase information varies over a wider range of values near a resonant frequency. By determining the second frequency according to the phase information the second frequency can be determined more accurately. A communication Having a more accurate second frequency improves the efficiency of the transmission from working energy to a transceiver, allows for a faster or more accurate identification of transceivers, extends the workspace the monitoring device, overcomes discussed above Problems with harmful Orientation or leaves a faster one or more accurate data transfer between the monitoring device and to a single transceiver.

If each transceiver has a respective identification number with a can have a consistent total of sections, a procedure for determining an identification number of a transceiver of several such transceivers include the steps of: (a) transmitting a start signal; (b) Receive a response at a time the start signal; (c) determining a number corresponding to that in Step (b) certain time; (d) transmitting a start signal and the in step (c) certain number; (d) repeating steps (b) to (d) until a number of executions of the sending step not less than the uniform whole; and (f) determining the identification number corresponding to each answer.

By repeating the transmitting steps a number of times not less than the uniform whole, a step of detecting whether a collision has occurred is not necessary. The answer can not convey more information than the fact that an answer has been given, thereby eliminating the need for a longer response time. By dividing an identification number into sections and using the protocol discussed above, there is practically a large number of unique identification numbers (e.g., 2 ⁴⁰ in 4 10-bit sections) without increased complexity or cost in each transceiver.

A short response time has several advantages. Several Answers can be received in a given period of time, reducing the probability The identification of transceivers is increased only briefly in the area the monitoring device are; redundant answers can be used for increase the system reliability be used; and those in each transceiver to send a response necessary amount of energy can be reduced.

One Lower energy consumption has several advantages containing: Transceiver with lighter weight, smaller size can with lower costs usable; and the communication area can by extension of the one used for receiving or sending or both Energy budget can be extended.

A Extension of the communication area has additional Advantages contained in: Enlargement of for communication for Transceivers, which are only briefly in the area, possible Time, decrease of the above discussed adverse effects of harmful Orientation; Allowing closer proximity between transceivers; Allow of larger numbers of transceivers in close proximity to each other; Reducing the size of antennas; and decrease in the number of monitoring devices or antennas that are otherwise to worry about communication in a big one Area are necessary.

The Method for determining an identification number can be a Step following Step (b) for discarding an invalid response. Farther can Time domain or frequency division techniques used in the process of determining a second frequency used in the method for performing transceiver communication can be in the process to Determining an identification number in the discarding step an invalid one Answer to be used.

One Transceiver can be a resonant circuit (with a resonant frequency), a receiver, a memory, a comparator, a counter and a transmitter included. The resonant circuit contains an antenna used for receiving and transmitting. The one with the resonant circuit coupled receiver detects a start signal followed by an indication of a first code. The comparator provides a comparison result as an answer to the first code and a second one supplied by the memory Code. The counter is loaded with a count provided by the memory and supplies completion signal after a period of time according to the count. Of the Sender sends a response in response to the comparison result and the completeness signal.

If the second code maps to a transceiver identification number, if such a transceiver identification number can be determined, without that Transceiver sends the second code. The duration of sending the answer is thus short with those discussed above Benefits.

If such a transceiver is used with the system described above and the resonant circuit is used to generate the frequency for transmission can be the first recipient the monitoring device optionally in a reduced frequency band, which is expected to that it contains the answer receive. This results in an improved receiver sensitivity with at the same time improved reception area.

One Transceiver can also contain a phase locked loop, which is based on the just received frequency switches on, the switched frequency in the absence of a received signal maintains and drives the transmitter to use at the retained frequency to send the resonance frequency. It can be an improved range of coverage be achieved by the transceiver. An improved communication can be achieved as a result of supplying working energy, Determine identification and for can provide a data transfer at a frequency different from the resonant frequency differs, especially if the resonant frequency discussed above adverse orientation is affected.

By Sending a response in response to the completion signal may be a numeric Value from the transceiver to the monitoring device with a numerical resolution be transmitted according to the duration of the start signal. For example can Transfer multi-bit digital values with a 1-bit response become.

A monitoring device may include a processor for communicating with multiple transceivers, an event detector, a plurality of receivers, a plurality of transmitters, and an antenna network controller for coupling the monitor to a dedicated antenna network. The processor may include first and second processors coupled for data transfer through a computer network. The processor may determine the location of a transceiver in a region monitored by an event detector in response to a signal provided by the event detector in cooperation with transceiver communication discussed above. Multiple receivers provide simultaneous narrowband detection for receiving a signal corresponding to a predetermined phase. Multiple transmitters provide for each of a plurality of simultaneous or sequential transmissions, each on a respective antenna (or group of antennas) and having a respective amplitude, frequency and phase that may differ from other respective transmissions.

One Antenna network in one embodiment according to numerous Aspects of the present invention includes multiple with an antenna bus coupled antenna nodes. Each antenna node contains several transceiver channels and a coupler for coupling each transceiver channel to one provided variety of antennas. Each transceiver channel contains one Squelch. If the squelch near a point in each of multiple antennas is related to noise reduced external band energy. In another embodiment contains the squelch multiple power sources for each branch of a to be blocked Antenna.

One Antenna network node in a further embodiment according to numerous Aspects of the present invention includes a cross-channel coupler and a transceiver channel which provides a differential amplifier for Signal processing in the vicinity of provided antennas.

One Antenna network in a further embodiment according to numerous Aspects of the present invention includes an antenna bus and a plurality Network nodes, each with a processor, a tuner and a Coupler for coupling provided antennas to the tuner. Of the Bus transports Signal indicating a command with settings. The processor leads the Operation of the tuner according to the settings. In a another embodiment promoted a head of the bus at a first time points to the Command and at a second time indications of a signal to be sent.

One Passage may contain planar antennas, each under one each angle are arranged to a minimum in combination provide a received signal greater than a predetermined one Value for all possible Orientations of a transceiver in the passage is.

In an alternative embodiment contains each antenna has a Q modifying circuit that has a broadband Reception as transmission facilitated.

One carrier can tune an antenna and a series of capacitors the antenna included. The result is an improved transceiver communication, if the transceivers in the carrier are placed. In an alternative embodiment, a carrier contains a first and a second antenna each with a respective tuning capacitor. The first and second antennas are coupled for cooperation. Energy received in a first pattern becomes in a second Pattern for a further improved transceiver communication aired.

BRIEF DESCRIPTION OF THE DRAWING

It will now be embodiments of the present invention with reference to the drawings in which like reference numerals denote like elements, and:

1 Fig. 10 is a functional block diagram of an object identification system relating to the present invention;

2 a functional block diagram of an exemplary embodiment of transceiver areas of objects 104 and 105 in the system of 1 is;

3 a graph of signal feature size versus frequency for the set of objects 102 to 112 in the system of 1 is;

4 a timing diagram of signals 170 and 172 in a transmission and response scenario of Systems of 1 is;

5 a flow chart of a method for data communication between a monitoring device and one or more transceiver (s) of the system of 1 is;

6 a flowchart of a method for performing the scanning step of the method of 5 is;

7 a flowchart of a method for performing the Subscanschrittes the method of 5 is;

8th a data flow diagram of processes performed by each transceiver in an exemplary embodiment of the system of 1 is;

9 is a panel describing the purpose and scope of numerous instructions given by a monitor and by a transceiver in the system of 1 be performed;

10 is a panel showing the structure and effect of a set of instructions in one embodiment of the system of 1 describes;

11 is a message format diagram describing message formats used to establish and perform data communication in an exemplary embodiment of the system of FIG 1 be used;

12 a flowchart of a method for performing the query step in the method of 5 is;

13 a flowchart of a method for performing the "send command and stack responses" step of the method of 12 is;

14 a flow chart of a method for performing the "list members" step of the method of 12 is;

15 5 is a timing diagram of query related signals in an exemplary embodiment of data communication for the system of FIG 1 is;

16 a timing diagram of signals for demodulating a received signal and for modulating a signal for transmission in a transceiver in the system of 1 is;

17 a functional block diagram of a rectifier of a transceiver as in 2 is;

18 a functional block diagram of a receiver of a transceiver as in 2 is;

19 a functional block diagram of an alternative detector for the receiver of 18 is;

20 a functional block diagram of a transmitter of a transceiver as in 2 is;

21 a functional block diagram of an alternative transmitter for a transceiver as in 2 is;

22 a functional block diagram of a state machine of a transceiver as in 2 is;

23 a functional block diagram of a memory of the state machine of 22 is;

24 a functional block diagram of a monitoring device of the system of 1 is;

25 a functional block diagram of a receiver of the monitoring device of 24 is;

26 a functional block diagram of a diode detector of the receiver of 25 is;

27 a functional block diagram of a synchronous detector of the receiver of 25 is;

28 a functional block diagram of a transmitter of the monitoring device of 24 is;

29 a functional block diagram of an antenna node of the system of 1 is;

30 a functional block diagram of an RF channel of the antenna node of 29 is;

31 a functional block diagram of a tuner of the antenna node of 29 is;

32 a functional block diagram of a squelch of the antenna node of 29 is;

33 a functional block diagram of an antenna network interface of the antenna node of 29 is;

34 is a panel containing numerous planar antennas with reference to the geometry of the passage of 35 describes;

35 is a plan view of a passage through which objects of 1 for the purposes of identification and control in an exemplary installation of the system of 1 can step;

36 a schematic diagram of an antenna of the system of 1 is; and

37 is a top view of a carrier that can be used to communicate for multiple objects of the system 1 to improve.

In Each functional block diagram represents a broad arrow symbolically a group of signals that together signify a binary code. For example, the output of a binary counter is indicated by a wide arrow reproduced as a binary number from the signals on multiple conductors, common at a time be removed, is marked. A group of signals without binary coded relationship can be considered a single line with an arrow be shown. A single line between function blocks transmits or several signal (s). Signals that appear in several figures occur and have the same mnemonics are by direct connection or by additional Facilities coupled together.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

An object identification system according to various aspects of the present invention provides for communication between a monitoring device and an object while the monitoring device and the object are within a communication range. Each object contains a resonant circuit coupled to an antenna used for communication. Communication, as used herein, may be used to accomplish one or more purposes, including: (a) detecting the presence of a resonant circuit (eg, to locate an object in an area), (b To provide working energy to a transceiver, (c) determine the resonant frequency of such a resonant circuit, (d) determine a transceiver identification, (e) receive data from a transceiver, or (f) transmit data to one or more transceivers (s) to send. Transmission energy levels may vary according to the range suitable for communication. For example, objects with a higher transmit power level may be detected and a warning may be issued that some objects may be outside of the polling area. Communication may be performed using the same or different media or frequencies for different purposes (eg, magnetic induction, radio, infrared, or sound). Different media or frequencies may be used simultaneously or at different times for the same purpose. When said objects are in proximity, the antennas may couple the resonant circuits to provide a common resonant frequency, which is typically less than the resonant frequency of each resonant circuit in isolation. In accordance with various aspects of the present invention, communication is accomplished overcoming the problems described above, which include varying the orientation of each object antenna and coupling effects (e.g., proximity of object antennas to one another and areas interfering with communication by reflection, absorption, or refraction ) are overcome. For example, the object identification system contains 100 a host 122 , a network 128 , Monitoring equipment 124 and 126 , Antenna systems 120 and 122 , Sensors 160 and 162 and control devices 164 and 166 , The system 100 can provide reliable communication despite interference from transmit sources that are not part of the system 100 are, manufacture. For example, sends a source of interference 190 (which is representative of a number of sources and locations) a signal 193 (which represents one or more frequency component (s) or noise) in the receiving area of the antenna systems 120 and 121 ,

The main computer 122 can be any computer system with computing capacity and interfaces to support data communication on the network 128 under one or more monitoring devices 124 . 126 contain. A conventional office computer system may be used. The main computer 122 can be operated to obtain notification of objects from the monitoring devices 124 . 126 have been detected or identified, and to perform any otherwise conventional business process in response to said message. As a representative example, the host may provide for materials accounting, point-of-sale service, materials management, automatic data collection, electronic goods control, or electronic access control in response to object detection or identification where objects may include ID cards, identification tags, transport tags, commodity labels, electronic keys, authorization devices, or price tags.

The network 128 may include any network for data transfer (eg, an Internet, a Wide Area Network, a Local Area Network using cable, voice, or wireless technology) between a monitor and a host. In addition, the network can 128 a data transfer between one or more monitoring devices 124 . 126 support.

The main computer 122 may perform a substantial portion of the data analysis, communication (eg, creation and analysis of messages to and from objects according to one or more protocols for determining identification), and control functions discussed herein with respect to a monitoring device if, for example, a monitoring device 124 . 126 has a limited processing capacity. In such an embodiment, the monitoring device receives 124 Commands from the main computer 122 and delivers reports to the host 122 over the network 128 , The commands can be requests from the host 122 regarding the current state of the controls 164 , the current readings from the sensors 160 , the state of any antenna node 140 . 142 and the state of the configuration of the monitoring device 124 or the antenna system 120 contain. The main computer 122 can the monitoring device 124 command to send on one or more desired frequency (s), the monitoring device 124 instruct to receive on one or more bands (wide or narrow) and / or perform analog and digital analysis of signals received from the antenna system 120 are received, and may be a reconfiguration of the monitoring device 124 , Sensors 160 , Controls 164 and / or the antenna system 120 instruct. Besides, the main computer can 122 , by appropriate commands, a message of detected objects or a list of object identifications currently in the communication area of the monitoring device 124 request and / or request raw data, of which the main computer 122 Detect objects or can determine such a list. Finally, the main computer 122 , using appropriate commands for the monitoring equipment 124 and 126 , a cooperation of the monitoring equipment 124 and 126 to perform any of the functions discussed above.

A monitoring device includes any system that communicates with one or more objects and provides results of said communications. Results may be provided to a user at the monitoring device (eg, when the host computer 122 omitted) or a host computer for processing discussed above. The system 100 may include one or more monitors using multiple monitors for redundancy, or when the capacity of a single monitor is exceeded by physically distributing objects or the desired amount of communication in an expected set of objects in perhaps a limited amount of time. For example, the monitoring devices 124 and 126 functionally equivalent and arranged in two geographical areas or territories. If no redundant communication with objects is desired by each monitoring device, the location of an object within a particular area may be determined by communication with one of the two monitoring devices 124 or 126 be determined. Movement of an object from one area to another may be by the host 122 of appropriate reports by the monitoring facilities 124 and 126 be determined.

An antenna system includes any system for coupling one or more antenna (s) to a monitor for communication between a monitor and a transmitter or more than one object (s). When communication from one or more monitors is limited to providing work energy, receive antenna functions from such monitors and antenna systems may be omitted. For example, contains an antenna system 120 for an above discussed communication, an antenna bus 132 , the one antenna node 140 and antenna nodes 142 with the monitoring device 124 coupled. The antenna node 140 supports antennas 150 , The antenna node 142 supports antennas 152 , The antenna system contains the same way 121 an antenna bus 136 for coupling the antenna node 144 and the antenna node 146 with the monitoring device 126 , The antenna node 144 supports antennas 154 , The antenna node 146 supports antennas 156 , As used herein, an antenna represents each transducer of energy used in the communication, including, for example, a lens for infrared light energy or a horn or structure for sound energy. An alternative antenna system includes one or more replaceable module (s) for reconfiguring the operation of any communication medium or frequency band to another medium or frequency band.

An antenna bus includes any network for transmitting signals for coupling one or more transmitters to one or more antennas, for transmitting signals for coupling one or more antennas to one or more receivers. and for coupling one or more processors / processors for data communication. For example, the antenna bus couples 132 the antennas 150 . 152 with transmitters and receivers of the monitoring device 124 , In addition, the antenna bus couples 132 Processors in antenna nodes 140 and 142 with a processor of the monitoring device 124 , The monitoring device 124 can be accomplished by issuing commands to one or more antenna nodes via the antenna bus 132 Instruct antenna node functions and receive status information. In an alternative embodiment, more than one monitor may use the same antenna bus. For example, the monitoring devices 124 and 126 for communication via the antenna bus 132 instead of (or in addition to) communication between monitoring devices via the bus 128 be coupled.

Communication between a monitoring device and an object may include one or more antennas. For example, a communication between the monitoring device 124 and an object 103 with signals 170 from the antennas 152 to the object 103 and a signal 172 from the object 103 to the antennas 152 shown. It is not necessary for the same antenna node to function for transmit and receive communication with a particular object. For example, the antennas deliver 152 a signal 174 to an object 102 and delivers the object 102 a signal 176 for reception by the antennas 150 ,

The Orientation of an object antenna, as discussed above, closes the Orientation of the object antenna with respect to one of a monitoring device Antenna used to communicate with objects and closes the orientation the object antenna with respect to other object antennas. When in the essential planar antennas in the monitoring device and can be used in the objects, a coupling of the antennas for energy transfer from a monitoring device on an object mainly done by magnetic fields. Such a coupling may decrease, if the object antenna orientation of coplanar (or parallel Levels) with respect to the surveillance antenna different. When planar object antennas are coplanar (or in parallel Layers) in relation to each other, an object can receive energy from Receive other objects and can be the coupling of several resonant circuits the behavior of one or more such resonant circuit (s) cause. For example, if every object has a resonant circuit a resonant frequency when operating in isolation, can be a group of objects an energy absorption peak at another (z. Lower frequency), herein as a stack resonant frequency designated have. Some objects in a stack can not to the same extent like others (eg a majority) objects can be coupled and thus can Energy at a frequency between the resonance frequency in isolation and absorb the stack resonant frequency of the majority more efficiently. In other words, a non-uniform stack of objects have multiple stack resonance frequencies.

The interaction of resonant circuits in such a system of coupled object antennas may have a detrimental effect on communication. Disadvantageous effects may include inadequate work energy being received by a particular transceiver in an object, so that other communication purposes can not be met; insufficient or discontinuous energy to support digital and analog functions (e.g., counting, measuring, converting) so that the data communication may be inaccurate; balanced region of a signal transmitted by an individual object and an expected energy spectral density deviating from one of an indi transmitted to the individual object.

The sensors 160 . 162 measure numerous aspects of the environment near each monitoring device while the controls 164 . 166 Change the environment. The sensors 160 . 162 For example, conventional electronic transducers including, for example, temperature sensors, pressure sensors, proximity sensors, electromagnetic sensors, optical sensors, and mechanical sensors may be used, such as detection of physical environmental conditions, movement of objects in a surveillance area, opening and closing of doors, and passage of doors Vehicles, animals, personnel and / or not equipped with transceiver items conventionally used. In one embodiment of the system 100 The sensors can be used for automatic data acquisition with regard to a POS terminal 160 . 162 a bar code reader, a video camera and other conventional product tracking sensors. The controls 164 . 166 may contain any conventional plant controls if the monitoring devices 124 . 126 are stationary; or, if necessary, vehicle controls for monitoring equipment 124 . 126 included in a mobile configuration. The controls 164 . 166 For example, controllers may be used to change the orientation of one or more antenna (s) of the antenna systems 120 . 121 contain. Each monitoring device 124 . 126 Integrates and reports information resulting from the sensors 160 . 162 detected events and communication with one or more object (s) 102 to 112 Respectively. Such reports may be provided by alerts, audible announcements, printouts or advertisements (not shown). Each monitoring device 124 . 126 can affect one or more detected events by changing the state of the controls 164 . 166 and / or reporting one or more events over the network 128 to the main computer 122 and / or respond to another monitoring device.

The sensors and controls discussed above may be used in an alternative embodiment of the system 100 from one or more antenna nodes in addition to or in place of the monitoring device 124 directly supported sensors 160 and 164 get supported. Supported by an antenna node, sensors and controls may be placed in locations remote from the monitoring device 124 are more suitable for signal forwarding, system installation, testing or maintenance. A node of such an embodiment may support any combination of antennas, sensors and controls, including configurations solely of antennas (as shown), sensors or controllers.

The system 100 can be constructed and assembled using conventional electrical and electronic components and techniques that include firmware and software developed using conventional software development techniques. Objects for use with the system 100 may be constructed and assembled using conventional electrical, electronic and mechanical techniques, the assembly as integrated circuits, hybrids, smart cards, tags, tags, badges, packaging materials, packaging, containers or signage as desired for any of the applications discussed above is included. Although the physical proximity of the objects for clarity in 1 is shown, the function block diagram of 1 not other physical aspects of the system 100 convey. There may be any of numerous spatial assemblies and distributions of the functions of the system 100 be used for a desired system operation using conventional package and data communication technology. For example, the functions of the host computer, the monitoring device and the antenna system may be integrated into one assembly or divided into numerous cooperating or redundant assemblies. The system 100 may be extended to include any number of host computers (one shown for simplicity), any number of monitors (two are shown for simplicity), and any number of antenna nodes per antenna system (two are shown for simplicity). The antenna system 100 may be integral with a single location, distributed in one or more areas or mobile. Similarly, the objects can 102 - 112 have relatively fixed locations (eg, embedded in roads, treadmills, etc.) when the monitors are mobile or portable.

The objects 104 and 105 make up stack 114 wherein respective object antennas are coupled to some extent (eg, more or less aligned in parallel planes or coplanar and / or positioned in more or less close proximity to each other). Similarly, the objects form 107 to 112 a stack 116 , For objects with planar antennas operating at 1 to 15 MHz, coupling sufficient to observe a stack resonant frequency different from the resonant frequency of an isolated object may occur at distances between parallel aligned object antennas less than 8 inches (eg, about 1 inch). The stack 114 from objects 104 and 105 acts as with reference to below 2 described, together. Every object 104 . 105 contains an identical transceiver 201 . 231 , The transceiver 201 contains an antenna 202 , a tank circle 204 , a rectifier 206 , a receiver 208 , a transmitter 210 and a state machine 212 ,

The tank circuit 204 is a conventional resonant circuit (eg, a series, parallel, or series / parallel resonant circuit). The inductance of the antenna 202 can with the tank circuit 204 as an additional inductance or as the main inductance of the tank circuit 204 interact. When they are near the antenna 232 is located, the antenna can 202 by generally at 290 be connected marked flux lines. The river lines 290 provide magnetic coupling between the antennas 202 and 232 The effects of magnetic coupling on the tank circuit 204 contain (a) change in the resonant frequency of the tank circuit 204 , (b) changing the Q of the tank circuit 204 , (c) loading the transmitter 210 when transmitting, and (d) attenuating any of the receiver 208 received signal (eg energy or message). When the tank circuit 204 Energy for the purpose of powering the transceiver 201 receives with energy, the magnetic coupling can be used for energy conversion from the rectifier 206 lower received energy. The tank circuits 204 and 234 act together when coupled (eg, ring currents in phase, a resonant frequency, referred to herein as the stack resonant frequency, and energy splitting). Special advantages are in the system 100 as a consequence of improving some of these effects and taking these effects into account in the monitoring device 124 and / or the host 122 accomplished functions. For a transceiver that is operable at 8 to 10 MHz (preferably at about 5.5 MHz), the tank circuit 204 have a Q in the range of 90-130 in isolation, 40-70 in coupling with the transceiver circuit, and down to 20 when in the vicinity of other transceivers. For example, a stack of from 3 to 100 transceivers in coplanar orientation may have a Q of about 35.

Each monitoring device 124 . 126 For example, at any appropriate time, a method may be performed for selecting one or more frequencies (or changing frequencies) for communication between the monitoring device and one or more objects. When selecting a frequency (or band) for communication, the monitoring device may 124 continue to detect, allow, interrogate or transmit data with one or more transceivers by transmitting and / or receiving messages using the selected frequency (or band). For example, a procedure 500 from 5 from the monitoring device 124 or through the cooperation of the host discussed above 122 and the monitoring device 124 be performed. A monitor may provide power to transceivers at any time for further communication (eg, prior to polling, interleaved during polling, simultaneously on a different frequency, or not at all for battery powered transceivers).

In step 502 For example, a sequence of frequencies in a desired scan area is determined and stored in a field with monitor transmit transmit frequencies, MTFS [1 ... A]. Such a sequence of frequencies may include any integer number of frequencies (eg, as indicated by variable A) and may be selected (or stored) from field MTFS in any suitable manner. Preferably, a sequence of frequencies is selected to avoid transmitting more than a predetermined average energy in any particular frequency band. A frequency range may be divided into any number of bands. Said bands may have any bandwidth, overlap, and may omit one or more parts of the range. The sequence of frequencies may provide for one or more transmissions in a first band, followed by one or more transmissions in any other band. For example, transmitting on a frequency in a first band (e.g., F308 in band F304 through F312) may be followed by sending any frequency in a second band (e.g., F324 in band F320 through F328) to the limit average energy sent in the first volume. A frequency offset from the beginning of a band may be used as an offset in another band; although different respective offsets can be used in each band.

To the Example may be any of the related patent application cited above S / N 09 / 088,924 described sequence of frequency transmission be used.

F ist die Mittelpunktfrequenz (z. B. in MHz);
F ± R ist der zu scannende Frequenzbereich;
2R/N ist der Frequenzschritt (z. B. in MHz);
N ist die Gesamtanzahl von Übertragungen in dem zu scannenden Bereich;
T ist die Gesamtanzahl von Übertragungen in einem Unterscan;
n ist die Frequenzzahl für jede Übertragung;
s ist die Unterscanzahl in jedem Scan; und
t ist die Übertragungsanzahl in jedem Unterscan.Scanning can be defined for an area around a central frequency, which is divided into an integer number of continuous bands with identical bandwidth. For the purpose of limiting the average energy sent in each band, scanning can be done in a number of sub-scans. Each subscan may include a broadcast in each band with an offset from the lower bound of the band. The sub-scan can be performed from band to band in sequential order of increasing frequency go. The offset used in a first subscan may be incremented by an incremental amount for use in a subsequent subscan. The number of sub-scans performed may depend on whether a frequency or candidate frequency of interest is detected (as discussed below); or the number of sub-scans may be equal to the number of transmissions to be made in each band. Given all the above constraints, the frequency used at each transmission can be expressed by the formulas: f (s, t) = [n (s, t) × (2R / N)] + (F - R)

F is the center frequency (eg in MHz);
F ± R is the frequency range to be scanned;
2R / N is the frequency step (eg in MHz);
N is the total number of transmissions in the area to be scanned;
T is the total number of transmissions in a subscan;
n is the frequency number for each transmission;
s is the subscan number in each scan; and
t is the transmission number in each subscan.

In the scanning technique described by the above formulas can be N, T, n, s and t for ease of calculation (eg, loop counter and Borders) be integer. Values for S and t can be consecutive as a whole Numbers are selected based on the series of integers, characterized by the limitations in the above formulas are.

In alternative scanning techniques can any rows instead of rows of integers, for example a number of real numbers are used. It can be any function used to be another To determine the value of the rows, including, for example, a pseudo-random number generator. If ribbons not treated consecutively, no equal bandwidth may or may not be continuous, may be any algorithm (for example, a look-up table or a set of rules) be to appropriate values for one for the next one to send Frequency to determine. In similar Way one can be used in each subscan for each band suitable offset determined by any suitable algorithm become. For example, a pseudorandom number generator may be used be to a next Band and another Offset for a next one Send in the band to determine. The amplitude and / or duration of each transmission may, for example, vary as a frequency function if the average energy in a reactive or resonant load (eg. B. a load that is not purely resistive) to limit is. Another one Frequency corresponding to a series or one discussed above Algorithm can be determined at a subscan as a result of a Predict the average energy transmitted in the band would, and a determination of whether a maximum average energy exceeded would, if the sending would not fail to be omitted. A Such determination may include consideration of prior transfers over a suitable period of time included.

If different working frequencies for discussed above various communication purposes can be used (eg, a Object a resonant circuit for receiving energy and a second resonant circuit to query), scanning frequencies in any sequence for determining any combination of Working frequencies of one or more objects are selected. For transceivers, the at isolation at about Working at 5.5 MHz, scanning can range in a range of about 2.5 MHz (eg F304) to about 6.0 MHz (eg, F328) to include manufacturing tolerances and object orientation (eg stack), as discussed above, Take into account.

The MTFS field may contain, for each frequency, values that specify the configuration to be used for transmission and reception. Such values may include configuration parameters for each transmitter (eg, energy level, synchronization, duration, one or more antennas, tuning and control phases) and for each receiver (eg, detector selection, selection of clock signals, filter parameters, synchronization, one or more antennas , Tuning, squelch timing and signal processing parameters as discussed below). For efficiency reasons, default values or references to sets with predefined values can be used. Filter parameters and / or signal processing parameters can be a se effective attenuation of interference (in the time domain or frequency domain), as in any previous embodiment of a process step 500 is determined. Since both the transmit band and the receive band can be specified for each entry in the MTFS field, alternative scanning techniques may be used which include: (a) transmitting a narrowband signal and receiving with a wideband detector; (b) transmitting a wideband signal and receiving with a narrow band detector; (c) transmitting two or more narrowband signals (consecutively or simultaneously) and receiving with a wideband detector; or (d) maintaining the transmission of a wideband signal while being received at successive times with different narrowband detector settings.

In step 504 a scan subroutine is performed according to the contents of field MTFS. Any suitable scanning method for determining one or more signal characteristics of candidate frequencies may be performed to facilitate selection of one or more frequencies for interrogation. Special advantages are in the system 100 by using a scanning method of 6 achieved. The controller can by step 504 on step 601 from 6 be transmitted.

In step 602 For example, the first monitor transmit frequency is selected for scanning from the field MTFS using a loop variable S associated with the first index value of 1.

In step 604 becomes an unmodulated carrier at the frequency indicated by the value MTFS [S] from the antenna system 120 (eg, one or more default antennas, or one or more antennas that, as discussed above, in step 502 have been determined) for a duration D430 which is in 4 as a signal 170 is shown. Carrier transmission begins at time T410 and continues until time T414. The rise and fall time of the unmodulated carrier can, as in 4 shown to be essential or (preferably) negligible. Duration D430 is preferably short compared to a START signal discussed below. A complete operation of the transceivers 201 . 231 is not required during scanning. In a preferred scanning method, carrier transmission is insufficient to provide work energy in each transceiver.

In step 606 may include one or more antenna (s) (eg, those used in the antenna system 120 to send the carrier in step 604 may be disabled) for a duration D434 to stop radiation that may interfere with receiving on the same or other antennas. The antenna blocking function is at or near the zero crossing of the signal, as shown at time T414 170 effective to avoid sending out-of-band noise. The locking operation is completed at time T416. The duration D434 is preferably less than a period in step 604 transmitted frequency (e.g., from about three periods of the transmitted carrier to less than 1 microsecond, preferably from 1 to 3 microseconds). Unused antennas are disabled or left open to detect an antenna resonance frequency in step 608 to avoid.

From the signal 170 Sent energy (such as a magnetic field) when transmitted from one or more transceivers 201 . 231 Consequently, an oscillating (ie calling) current in the tank circuits is received 204 . 234 and antennas 202 . 232 develop. Each oscillating current will continue as a consequence of the Q of the tank circuit after time T414. For example, a ringing signal, as an oscillating current through the antenna 202 occurs from the antenna 202 from time T416 to time T422. The signal 172 from 4 represents approximately the extent of the call signal. When flow lines 290 Coupling one or more tank circuits, all coupled tank circuits act together. As a result, the signal 172 the superposition of signals from one or more separate objects and / or one or more stacks as described above. The signal 172 is typically several orders or greater in amplitude than the signal 170 , The signal 172 may also be in the frequency and in the phase of the carrier signal 170 differ. These frequency and phase differences as well as changes in the amplitude of the signal 172 between times T416 and T422 convey information about the tank circuit 204 , about the orientation of the transceiver antenna 202 in relation to the antenna system 120 and other transceivers, the number of simultaneously-calling tank circuits, and possibly the location and relative movement (eg, within a region) of tank circuits relative to the antenna system 120 ,

In step 608 becomes the signal 172 from the antenna system 120 (eg, one or more default antennas or one or more antennas, which, as discussed above, in step 502 are determined) and sampled for durations D436 between times T416 and T418. Although a shorter amount of time may be used, the duration T416 through T418 and the sensitivity of the receiver (at expected signal levels to be received in a particular application) are selected to provide approximately 8 periods of the ringing signal for sampling. A number of sampling points 417 is in the monitor Recei ved scan field MRS [1 .. D] recorded. Each sample point may have an amplitude of the signal 172 (for example, a measured analog voltage converted to a digital representation). In addition, sample points may be taken at time T418 through T422 for further analysis.

In step 610 Numerous signal characteristics corresponding to the contents of the field MRS and similar fields corresponding to the earlier executions of the step 610 certainly. Any conventional signal feature may be determined. A particular signal feature may be determined at a first time (A) and again at a second time (B) (during the expected fall time of a paging signal) and the relationship between signal feature values at A and B may be used to determine a third signal feature. The analysis of signal characteristics can take place in the time domain (eg amplitude, phase) or in the frequency domain. Frequency domain analysis may be derived from the result of a conventional Fast Fourier Transform (FFT) of a series of sampling points (eg, a sampling window of 5 to 50 μs) beginning at time A (eg, time T416 for 5 μs). and / or starting at time B (eg, time T418 for 5 μs). Examples of suitable signal characteristics are described in Table 1. In an alternative embodiment, sample points are taken at a further time C after time B. Values of sample points at times A and C are then divided by dividing (eg, A '= A / B and C' = C / B) or by subtracting (eg, A '= A-B and C' = B - C) normalized. The times A, B and C are arranged at equal time intervals within the expected duration of a response signal or response signal.

TABLE 1

In step 612 Everybody gets in step 610 certain signal feature stored in a field with an index position, the frequency sent in step 604 equivalent. For example, multiple fields for monitor response signal characteristics may be indexed using the loop variables S as MRSP1 [S], MRSP2 [S], etc.

In step 614 the loop variable S is incremented and a subsequent monitor transmit frequency is selected until all monitor transmit frequencies have been transmitted. If a next supervisor transmit frequency has been successfully selected, then control goes to step 604 Ahead; otherwise the control goes 616 for a return to a call routine, for example, following step 504 , further.

In step 506 For example, fields MRSP1, MRSP2, etc. are analyzed individually and / or by comparison and / or correlation to determine which frequency or frequencies coincide with maximum values of a figure-of-merit based on one or more signal characteristics. The correlation can be time or spectral coherent. For example, if a figure of merit is only on a single signal feature, as in 3 4, conventional field analysis may be used to determine that the frequency F324 matches a maximum signal feature S384. Here the in 3 shown graph of values in memory as a list (or field) with frequency-feature pairs containing, for example, (F304, S360), (F308, S380) and numerous pairs in between. Peak values of the signal feature can be mentioned in the analysis, including frequencies F308, F312, F316 and F320. Further analysis may determine one or more candidate frequencies in accordance with conventional profile recognition logic and profiles of expected signal characteristics based on theoretical models, measurements, and analysis. For example, if frequency F324 matches the expected tank frequency for a custom transceiver, then frequency F324 would be a candidate. By profile recognition can be determined that the frequency F320 with the stack 114 matches and frequencies F308, F312 and F316 with the stack 116 can match. Using the normalization signal feature value S384, one can determine that the signal feature value S380 corresponding to the frequency F308 is also a candidate because its relative amplitude meets or exceeds a threshold. However, the signal amplitudes S378 and S374 corresponding to the respective frequency F312 and F316 may be due to the possibility that these smaller peaks in the signal feature value with object 107 and 112 (or similar objects) with weaker coupling to all other objects 108 to 111 of the pile 116 due to the positioning at the respective ends of the stack 116 may be of little interest. In other words, frequencies F308, F312 and F316 can be used with a single stack 116 which can be interrogated with a single frequency, for example frequency F308. For example, communications at frequencies F312 and F316 may be intentionally performed for one or more purposes (eg, sending power) when each frequency is expected to correspond to one or more other transceivers (for example, one for some reason). including proximity to another transceiver or to a surface that interferes with communication as discussed above, detuned transceiver).

In addition to the analysis of maximum values of in 3 A further analysis may consider the Q (eg, figure of merit or standard deviation) of the signal feature at each peak frequency. For example, the signal feature at frequency F324 has a high Q; the signal characteristic at frequency F308 has a slightly lower Q; and the signal feature has a relatively low Q at frequency F320. Some frequencies initially considered as candidates may be eliminated if the value of the signal feature (or figure of merit) does not correspond to a Q greater than a minimum expected Q or the relative magnitude of the signal feature does not exceed a minimum expected size. In the case of the pile 106 Having a signal characteristic with multiple peaks represented at frequency F308, F312, and F316, another analysis may be used to determine which of the three possible candidate frequencies is most appropriate for the query.

In a controlled environment Signal characteristics the number of existing objects, improper orientation of one or more objects or improper distance between objects Show.

In step 508 For example, one or more candidate frequencies may be subjected to further analysis in conjunction with a subscanning procedure. For each candidate frequency, a suitable range of frequencies near the candidate frequency is specified for a subscan. Any subscan procedure can be used. Special advantages are in the system 100 by performing the sub-scan procedure in a manner similar to that described above with reference to step 504 discussed scan procedure resembles. For example, the control of step 508 to step 701 from 7 pass. Frequency values specified in the MTFS field for a subscan may be from any of the configuration values (eg, checked for this subscan) described above with reference to step 502 be discussed.

In step 702 a sequence of frequencies within each desired sub-scan range is determined. Values are determined in a field with supervisor transmit frequencies for scanning, for example MTFS [1 .. C]. A typical sub-scan can span a frequency range of ± 200 KHz include a frequency of interest.

In step 704 a scan procedure is performed according to the contents of field MTFS. The controller can step to 601 go over and, as described above, by step 616 to return.

In step 706 verified signal feature fields MRSP1, MRSP2, etc. are used to verify one or more figure of merit factors as described above with reference to step 506 discussed. The controller returns to step 708 to the call routine, for example, step 501 from 5 back.

In step 510 For example, each frequency associated with a figure of merit of a suitable size is identified in a field with supervisor transmit frequencies for interrogation, for example, MTFI [1 .. B].

In step 512 each polling frequency is used in the conduct of a polling scenario. Any query protocol and modulation scheme will be used. Suitable query protocols are described in TABLE 2. A query log for use in the system 100 includes some conventional protocol for the transmission of an individual identification from a transceiver to a monitoring device as well as any protocol by means of which a monitoring device can determine an individual identification. A subsequent communication using the individual identification may then proceed without collision, interference or ambiguity in system operation. Any message format and modulation scheme may be used, preferably narrow band modulation, for example, any pulse width modulation (PWM) technique.

transceiver identification The frequency (or frequency band) in which a communication is reliably established can be a code or a sequence of codes by the Transceiver detected to enable one or more responses be a code displayed in (or through) an answer or contain a combination of these features.

TABLE 2

Special advantages are in the system 100 using the in the 12 . 13 and 14 described query procedure 512 achieved. The controller can by step 512 to step 1201 with reference to 12 pass.

The selected frequencies in step 510 may be used for interrogation, or alternatively, these frequencies may be for transmitting energy from the monitoring device 124 on one or more objects 102 to 112 be used. In the latter case, the interrogation may be in any conventional manner at any suitable frequency. For example, an object having a tank circuit that interacts with the tank circuit of nearby transceivers may receive energy from its radiation at a frequency that is near the resonance frequency of the tank circuit. In addition, such a transceiver can respond and participate in a polling scenario with a different frequency (eg, 250 MHz to 350 MHz) using conventional RFID. For example, the polling protocol and transmit modulation techniques used in conventional RFID include frequencies selected for appropriate propagation characteristics, infrared and other optical frequencies, and ultrasonic and other sound frequencies. Magnetic coupling between adjacent transceivers as described above with reference to FIG 2 can be described on any for the dimensions achieved by antennas and distances between antennas for the desired communication purpose suitable frequency. Magnetic coupling is preferred for providing an energy signal to limit the range of the energy signal and to meet execution guidelines.

modulation techniques contain, for example, scatter spectrum, amplitude modulation, frequency modulation, Single-sideband modulation and interrupt keying (Off / On Keying (OOK)) - modulation. OOK is due to its narrow frequency spectrum preferred, that a communication in presence and orientation from other objects that allows Absorb parts of broadband modulation to an unpredictable extent.

The complexity of circuits and firmware to perform the functions of a Transceivers can be obtained by using one or more of the following Techniques in combination can be reduced: (a) receiving working energy for the Receiver over the Antenna and the tank as described above; (b) Use of transceiver detection (eg, detecting a call signal) on the same frequency that is used to power the transceiver with energy; (c) Use from OOK modulation to the query; (d) Perform a query on it Frequency as used to power the transceiver becomes; (e) limiting the response of a transceiver during the Query (eg one or two bits); (f) using several in advance fixed answer slots for multiple transceivers for responding to a single command; (G) Use predefined durations of an unmodulated carrier for one or multiple transceiver reset operations; (h) Use a transceiver identification number with sufficient resolution for the practical reduction of the possibility from collisions in an expected operating environment to a negligible one Measure (z. Possibly to zero); (i) Using a protocol that identifies when a response corresponds exactly to a transceiver, without relying on collision detection mechanisms to support; and (j) using a N-part divided transceiver identification number and Use a protocol to discover part of an identity in more as another sequence of query messages.

The functions of the monitoring device 124 and the transceiver 201 will be described below in an embodiment that includes all of the techniques listed above. Although any embodiment of hardware, firmware (eg, state machine microcode) or software (eg, microprocessor instruction code) may be used to perform the portion of the protocol associated with the transceiver, an example embodiment supports the query and also read / write data communications. For example, the process 800 from 8th from a transceiver 201 be carried out to support such a protocol. The process 800 contains processes for the detection of START and SEPARATOR signals 802 ; Expecting an access code 804 ; Change an access condition 810 ; Comparing an access code with an access code from the memory 806 ; Sending a response in a reply slot according to an access condition 812 ; Expecting a command 814 ; and sending a message 816 ,

These Processes can in any combination of software, firmware or logic circuits supports become. Execution These processes can be in an interrupt driven, polled, catchy or parallel multitasking execution take place. As discussed below, a process reports one further process in any conventional Way, for example, using a common variable, Issuing a command, generating a signal, etc.

The process 802 continuously analyzes a received carrier for indications of a START signal and SEPARATOR signal. An uninterrupted, unmodulated carrier for more than a first predetermined period of time may indicate a START signal. When a START signal is received, the process may 804 be informed. When a START signal is detected, the state of the transceiver should be reset to a known initial state. The process 802 provides such a message to the process 810 to reset the access state. An uninterrupted, unmodulated carrier for a second predetermined duration (preferably less than the first predetermined duration) may be used to display a SEPARATOR signal. A SEPARATOR signal used herein may indicate an interrupt in a message, thereby indicating the beginning of a subsequent message. Upon detection of a SEPARATOR signal, the process provides 802 a message to the process 812 to terminate any transmission that may be in progress or transmission. The process 802 until trial 812 provides messages to reset the slot counter accordingly. Failure to receive a suitable START signal may cause the transceiver to fail 201 stay in a switched-off state. In the event of a failed attempt to receive a suitable SEPARATOR signal, the transceiver may be left to complete the current one Message format to expect.

The process 804 examines an incoming demodulated carrier from a START signal to a predetermined time when an access code is expected according to the message format. One of the process 800 The supported protocol divides the individual transceiver identification into one or more access codes. Each access code is associated with a so-called level code, which is to be discussed below. The process 804 forwards the received level code and access code to process upon receipt 806 ,

The process 806 works on a valid received level code and access code when coming from the process 804 to be delivered. The process 806 uses the level code as an address or an index in one of the memory 808 stored field for retrieval of a stored access code. Further, the process compares 806 the stored access code with the received access code and it provides results of the comparison to the process 810 in many of the process 800 supported protocols. Note that it may not be necessary for the access codes to be received in any particular sequence as far as each access code is received with an associated level code, which facilitates the retrieval of a suitable access code from the memory in accordance with the level code. Alternatively, as discussed below, any suitable sequence may dictate a desired access state change.

The process 810 changes the access state of the transceiver 201 , In response to a "reset state" command (or signal) from process 802 puts process 810 all access state bits back. If a suitable comparison result of process 806 can receive the process 810 set one or more access state bits. Preferably, the process continues 810 an access state bit in accordance with that of the process 804 provided level if a suitable comparison result indicates that the received access code exactly matches the stored access code. Numerous alternative protocols permit or require that an access state bit be set if a comparison result indicates any conventional relationship between the received access code and the stored access code (eg, <,> =, <, <= within a range, etc.). The process 810 returns the current access condition to the process 812 and may, upon receipt of a predetermined access condition, the process 814 command to start a command / response session.

The process 812 is activated for sending when the one from the process 810 provided access state meets or exceeds a pre-established activation access state (ie, the transceiver has been addressed in some measure defined by the protocol). The process 812 wins a slot number from the memory 808 in accordance with that of the process 804 provided layer code again. According to one of the process 800 supported preferred protocol, slots (marked with predetermined numbers) follow the occurrence of a START signal with a predetermined delay. After elapse of the predetermined delay time, the transmission process counts 812 preset slot durations (or slot boundary signals) until the slot number is achieved. The process 812 thereafter sends a response signal in the slot corresponding to the slot number retrieved from the memory. By sending a response signal in a predetermined response slot, the process provides 812 as performed in several identical transceivers, a response that, upon receipt by monitoring device 124 , indicates that one or more transceivers have been activated to transmit as a result of receiving one or more suitable access codes.

Each access code may represent a group (or subgroup) identification number. In a hierarchical arrangement, the individual transceiver identification may consist of a (GID) number, a subgroup identification number (SGID), a sub-subgroup identification number (S ² GID), etc., up to any number of levels. For example, if each access code represents a 10-bit binary number and four levels are used, an individual transceiver identification number consists of a 40-bit binary number. This identification number is sufficient to uniquely identify more than one million transceivers in each of more than 1,000 independent operating environments. Each operating environment is identified by a 10-bit group identification number (e.g., a top-level access code) having 30 bits remaining for identifying individual transceivers.

The process 814 when reporting a "start session" command, results in a process 810 , any suitable command / response protocol that is in the structure and function of the above with reference to the processes 802 to 812 described in the query log. The command / response protocol may be commands for sending data to a transceiver and for receiving response data from a transceiver over the above with reference to the process 812 received 1-bit transmission capability. The process 814 can receive data in the memory 808 Save and send a command to a process 816 deliver. The process 814 may continue for multiple command / response changes until: (a) the working energy is no longer from the monitoring device 124 is provided (or commanded to be withdrawn); (b) a command addresses and changes one or more enable access state bits in one or more transceivers; or (c) the completion of a command by a transceiver is accompanied by an automatic change of one or more enable access state bits.

The process 816 receives a command from the process 814 and can in the memory 808 retrieve stored data and / or receive measurement data from a conventional sensor (not shown). Data from the memory and / or one or more sensors may be passed through the process 816 in any suitable manner according to the protocol discussed above with reference to a query, the protocol discussed above with reference to a command / response session, or any conventional protocol.

In one embodiment of the system 100 , where data transfer to and from a transceiver beyond the ability to identify the transceiver is not required, the processes can 814 and 816 omitted and appropriate simplifications to the process 810 be made. On the other hand, one of the process 800 supported protocol include a variety of commands as described below with reference to 9 discussed. For the purpose of interrogating and identifying an individual transceiver identification, the commands 904 and 912 represent a minimal configuration.

The commands 902 . 904 and 906 affect the access state of a transceiver. The command 902 resets an access state bit. command 902 can be omitted in a simplified variant in which a reset of all access state bits is performed by adjusting the supply of working energy to a transceiver. Because energy from the monitoring device 124 supplied by broadcast carrier, is in some embodiments of the system 100 the need to reset one or more particular access state bits in a group of transceivers or in a transceiver without affecting the access state of unaddressed transceivers. The command 902 in combination with one or more access codes, the means for resetting one or more access state bits, as defined in a conventional manner, will provide for appropriate additional codes accompanying (or integral with) the instruction.

The command 904 is used to set an access state bit in one or a group of transceivers. As discussed above, the command 904 be used to accumulate a sufficient number of required set access state bits to complete the process 812 to activate. In a variation of the query protocol discussed above, the command 904 may be used to set any arbitrary pattern of access state bits, perhaps in a predetermined sequence, to facilitate any communication purpose discussed herein.

The command 906 is used to clear the slot counter in all transceivers. By clearing the slot counter, this command ensures that no further responses from transceivers are attempted without the occurrence of a subsequent command, possibly containing additional access codes necessary to obtain the process's operation 812 sufficient access condition. The command 906 can be omitted in a system embodiment in which no message is terminated before the message can go to completion. In a command 906 efficiencies can be achieved by clearing the slot counters once all expected (or significant) responses have been received.

The commands 908 and 910 perform the sending of data to transceivers from the monitoring device 124 by. The command 908 can be used to get data from the monitoring device 124 for storage in the memory 808 in one or an addressed group of transceivers. The command 908 may require a prerequisite access state for group identification, security or reliability purposes. The command 910 can be used to configure one or more sensor configuration registers to control any conventional aspect of sensor operation (eg, the timing at which a measurement is started, the duration during which a measurement is taken, the resolution or accuracy of the sensor) Measurement, indication of any measurement analysis, etc.).

The commands 912 to 920 can be used to receive data from a transceiver. The command 912 can be used in the query profile discussed above to address the existence of an address th transceivers. In response to the command 912 For example, a transceiver may respond with a 1-bit acknowledgment in a reply slot that corresponds to the particular affiliation of the transceiver. For example, if a group of transceivers is addressed, each transceiver can respond with an acknowledgment in a respective response slot that corresponds to the affiliation of the transceiver in a particular subgroup of the group. When fully addressed (ie no subgroup is defined below the lowest level of the current state of the query scenario), the transceiver receive command may be used 912 respond with an acknowledgment in a respective answer slot corresponding to its identification number (eg the least significant portion of the identification number, ie a member identification number). As discussed above, the command 912 with the command 904 combined to the effect that, if an answer to the command 912 is given, an access state bit is also set. Special advantages are in the system 100 by providing the command 912 in a form with the setting of an access state bit (as in command 904 ) and in another form in which no access state bit is affected.

The commands 914 and 916 may require that the instruction be addressed to a transceiver that has been completely addressed to ensure that only a transceiver will attempt to respond to the instruction. For example, assuming data from memory and sensor data exceeds one bit in length, then a transceiver may use data from its memory in response to the command 914 respond (or can a transceiver with sensor data in response to the command 916 answer) without collision, only if the monitoring device 124 identified a transceiver to transmit the data and completely addressed only the transceiver. The length of the data to be delivered in one or more responses to commands 914 and 916 may vary. Without departing from the general structure of a series of response slots, as discussed in the query protocol discussed above, up to 1,000 bits of memory or sensor data could be sourced from a transceiver in response to a single command 914 or 916 to be provided. Said data may be provided in a redundant or differentially redundant format for reliable reception by the monitoring device 124 sure.

The commands 918 and 920 Request a response from one or a group of transceivers. The answer to the command 918 For example, a dibit, two redundant bits or a short sequence of bits (eg, preferably one bit) may exist in each response slot corresponding to data from the memory. In a system with 1,000 response slots, 1,000 transceivers can respond with one bit each time until all data bits have been provided from the memory. In the same way, the answer to the command 920 Provide data from up to 1,000 sensors with one bit per sensor in each answer slot. In an alternative protocol are the commands 918 and 920 directed to a fully addressed transceiver. Such a transceiver provides a response from which a 10-bit memory value or sensor value can be determined. By answering in a response slot corresponding to the appropriate value (eg, 1 to 1,000), a 1-bit response specifies a decimal number to a part in 1,000. If 1024 response slots are used, a 1-bit response will convey a 10-bit binary value. A command / response session may be used to perform one or more of the functions described in Table 3.

TABLE 3

One or more of the commands related to 902 to 920 The purposes described above may be determined by certain message formats in a set of messages that are intended for use in a particular installation of the system 100 are optimized to be met. For example, command formats 1004 to 1007 from 10 sufficient to provide polling and identification of up to 1 million transceivers in 1,000 applications, as discussed above. Special advantages are in the system 100 by extending the instruction sets to command 1000 to 1003 from 10 contained, achieved. The extended instruction set may be used during a query, assembly, or test to determine, for example, a 40-bit transceiver identification number without going through a hierarchical query sequence become. For example, each command returns 1000 to 1003 an argument identifying a group identification number. No prerequisite access state bits need to be set. No access state bits are set as a result of receiving the command. In addition, the response from each transceiver is similar to that with reference to the command 912 described except that transceivers with a subgroup identification number on the command 1000 to be answered; with a sub-subgroup identification number on the command 1001 to be answered; with a sub-subgroup identification number in response to the command 1002 to be answered; and a sub-sub sub-sub-group identification number in response to the command 1003 to be answered. The commands 1000 to 1003 can be used to (a) determine or confirm the complete identification of a physically isolated transceiver; (b) determine or confirm all or part of an identification number of a transceiver when all other transceivers have been disabled; (c) quickly estimate the number of transceivers within a communication area; (d) the ability to quickly detect that transceivers have moved in or out of the communications area; or (e) confirm that a particular subset of transceivers are not within the communications area.

Unlike the commands 1000 to 1003 that do not set an access state bit set the commands 1004 to 1007 each a suitable access state bit. In addition, the commands can 1005 to 1007 reset the transceiver access state logic if the prerequisite state bit is not already set.

In an exemplary query scenario, the command becomes 1004 first provided with a level 1 group identification number to obtain information regarding level 2 subgroup memberships of all addressed transceivers. The answer slots show the level 2 subgroup identification number of this transceiver addressed by the group identification number. In addition, the status bit B0 of the access state logic is set. The level 1 group identification number is preferably a 10-bit access code. The level 2 subgroup identification identified by a reply slot indicates a 10-bit access code. Second, the command returns 1005 the level 2 subgroup identification number as its argument and determines the level 3 sub subgroup identification number of addressed transceivers that are members of the group identification and subgroup identification, as by the prerequisite state bit B0 and successful comparison of the provided subgroup identification number and the level retrieved from the memory 2 access code is displayed. As a result of a successful execution of the command 1005 Transceivers that are members of the group and subset will set state bit B1 corresponding to level 2. Third, the command 1006 with level 3 sub-subgroup identification number as an argument. Transceivers with successfully executed commands 1004 and 1005 the prerequisite state bits B0 and B1 will have been set. An answer to the command 1006 returns the level 4 sub-sub-sub-group identification number indicated by the corresponding numbered answer slot. In addition, the access state bit B2 becomes level 3 set. Fourth, the command returns 1007 the level 4 sub-sub-sub-group identification number as the argument and, in the respective answer slot, retrieves the member identification number of these transceivers indicating the comparison of the group identification number, sub-group identification number and sub-sub-group identification number by setting the required status bits B0, B1 and B2 are, and further, the successful comparison of the command with 1007 delivered sub-subgroup identification number and the level 4 access code retrieved from the memory. The transceiver who is at the command 1007 has successfully responded will also set the access state bit B3. A system manager of a system 100 may arrange transceiver identification numbers to ensure that the commands are correct 1004 to 1007 supplied identification number will always address exactly one transceiver. In one the commands 908 . 910 and 914 to 920 supporting variation of the system 100 can the command 1008 with a suitable argument for reading or writing data in the memory or a configuration register of a transmitter or for reading data from a sensor or from a memory as discussed above. An answer to the command 1008 (eg in a particular answer slot) may provide a write acknowledgment or, as above with reference to command 918 and 920 to deliver a 10-bit data value from a sensor or location. Another set of access state bits may be for the instruction 1008 be unnecessary. In a variant, further access state bits may be defined and by numerous commands from above with reference to the command 1008 be set to perform more sophisticated transceiver functions.

The referring to 10 Commands and arguments discussed may be arranged in message formats in a conventional manner. Special advantages are in the system 100 according to various aspects of the present invention using the message formats of 11 achieved. For example, one out of a command 1101 identifying binary code existing message format 1100 used to get the commands 902 and 904 perform. These instructions do not require an argument if the instruction identifier code implicitly identifies one or more access state bits.

A message format 1110 can for the commands 914 and 916 be used. The message format 1110 contains command identifier code 1111 , Padding mark 1113 and answer bits 1114 , If used, the pad will separate 1113 expediently command code 1111 of answer bits 1114 and provides reliable detection in the transceiver of the first response bit of response bits 1114 for sure. reply bits 1114 may contain any number of bits in serial format.

A message format 1120 can for commands discussed above 912 . 918 and 920 be used. The message format 1120 contains command code 1121 , Padding mark 1123 and answer slots 1125 , The answer slots 1125 identify numbered time periods. Each slot is used for a response. An answer may consist of one or more bits, but 1-bit answer slots are preferred. In an alternative answer slot configuration, a 1-bit response may be presented as a dibit consisting of the response bit in both true and complementary form.

A message format 1130 contains command code 1131 , Argument 1132 , Padding mark 1133 and answer slots 1135 , The argument 1132 can be any binary code. For example, the argument 1132 as discussed above, transmit a level code and an access code.

A message format 1140 can be a command code 1141 , Argument 1142 , a padding symbol 1143 and a separator 1146 contain. The separator 1146 may, as discussed above, contain a continuous, unmodulated carrier. In contrast, the padding character 1143 contain a period of time during which no carrier is sent.

In the message formats described above, the command codes 1101 . 1111 . 1121 . 1131 and 1141 an identical structure. In the same way, the Auffüllzeichen 1113 . 1123 . 1133 and 1143 have an identical structure and can provide a delay for processing a received command and argument. The answer slots 1125 and 1135 have an identical structure and function. The arguments 1132 and 1142 may have an identical structure or, if desired, vary and be indicated by corresponding command codes.

An example of a method for performing a query on interrogation frequency of a monitoring device according to step 512 will be down in the context of the process 800 presented in every transceiver. The controller may be of the step 512 to step 1201 from 12 to carry out the polling procedure of 12 to 14 pass.

In step 1202 Three variables are set to initial states. A variable C is set to 0 to indicate that a command of the form 1000 from 10 is to spend. A variable RS is set to 1 to indicate that a first response stack is to be used to store responses. A variable G is set to a group identification number of interest. A variable G, as discussed below, may be a suitable structure for many values. If a group identification number is used, this is one of 1000 installations of the system 100 may differ, the group identification number may correspond to a customer number, geographic area, political territory, and / or any indication that uniquely specifies this installation for the purpose of eliminating confusion with transceiver identification numbers that are correct elements of another system installation. The commands 1000 to 1007 are each identified by values 0 to 7 of the variable C.

In step 1204 a subroutine is called to send the command and store the responses on a suitable stack. The controller is going to move 1301 from 13 above.

In step 1302 will be a message in a format 1130 from the monitoring device 124 sent, with the command code 1131 is set to the value of variable C (initially 0) and the argument 1132 is set to the value of the variable G (initially the group of interest).

In step 1304 For each response slot in which a response is detected, a value indicating that a response has been detected may be stored on a stack identified from a field of stacks indexed by the variable RS. By providing a field of stacks, the query is the same A tree search algorithm, wherein up to 1000 responses are cataloged at each node. Each stack thus matches one of the nodes crossed in a modified depth-oriented tree search. In step 1304 For example, information associated with each response may also be stored on the appropriate stack. Such information may include: (a) the reply slot number; (b) Signal amplitude sampling points 417 ; (c) frequency domain results of one or more Fast Fourier transforms of sample points 417 ; (d) one or more signal characteristics; and (e) one with reference to the above 3 and 4 discussed quality factor. For efficiency, pointers to such information may instead be stacked.

In step 1306 Control returns from the send / batch subroutine to step 1206 from 12 back.

In step 1206 the variable C is set to 3 as an initial state for those in step 1208 called subroutine set.

In step 1208 a subroutine is called to list member identification numbers. This subroutine represents a recursive subroutine that performs the modified depth-oriented tree search discussed above, starting with the current value of the initially set variable RS. The control goes from step 1208 to step 1401 from 14 above.

In step 1402 it is determined whether the variable RS is at a maximum value. The variable RS shows, as with reference to 8th described, a level code. After the command 1004 already at step 1204 RS is set from the value 1 to a maximum value of 4 as described with reference to FIG 10 discussed commands 1004 to 1007 progress. After the control of step 1208 has been accepted, the test in step 1402 Fail and the control will go to step 1406 continue.

In step 1406 the variable G is assigned the value (or values) taken from the top of the stack [RS]. In an alternative embodiment, the access code to be used for the value G is obtained from a table look-up operation (eg, code conversion mapping). For example, the number of answer slot is used as an index in a field, and the value from field G is assigned for use as an access code. In an embodiment in which subgroups are not addressed in strict order of depth, a level code may be used as part of the index, and the field value may identify an appropriate level code in addition to the access code.

In step 1408 determines if the process 1208 has advanced to the end of the stack [RS]. If so, the controller goes to step 1402 for a return from this particular call to the recursive "list members on" subroutine. If not, the controller goes to step 1410 further.

In step 1410 the validity of the value (or values) of the variable G is determined. This validity test may be performed in a manner that is similar to determining whether a particular response represents a candidate frequency, as in step above 506 and 510 is described. This analysis may include an analysis of time domain results, frequency domain results, signal characteristics and quality factors, provided that sufficient information has been stored on STACK [RS]. A time domain analysis may include the received signal or features (eg, rise time, fall time, envelope shape, or peak time relative amplitude) with expected values or characteristics corresponding to the Q of the tank 204 and below referring to signal REPLY of 16 compare energy limitation features discussed. If it is determined that the variable G does not represent a valid transceiver, then control goes to step 1406 back to get another value from STACK [RS]. Otherwise, the control goes off step 1410 to step 1412 further.

In step 1412 the variables C and R are incremented respectively. Increasing the value of the variable RS stores results on a new (empty) stack. By increasing the value of the variable C, preparations are made to send a command at the next level.

In step 1414 becomes a "send command and stack responses" subroutine 1204 out of context with the current level and in step 1412 specified current command called. When returning from step 1306 the controller goes to step 1416 above. In the first call to the subroutine 1204 from routine 512 can the message format 1120 , or preferably 1130 , be used. In subsequent calls to step 1414 can the message format 1130 alone or preferably prefixed by any suitable number of message formats 1140 be used. If used, preset message formats 1140 ensure that proper access state bit requirements through contents of respective arguments 1142 be fulfilled. Prerequisites may have been reset by loss of power or by resetting discussed above.

In step 1416 a recursive call is made to the "list members on" subroutine associated with the current value of the RS variable. The controller is going to move 1401 over and returns at the completion of step 1420 back.

In step 1417 variables C and RS are decremented to reflect the context of the current execution of the recursive "list members on" subroutine 1208 save. It continues processing in steps 1406 to 1417 loop until all responses from STACK [RS] have been considered. When all responses have been considered, control goes off step 1408 to step 1420 over and returns to an earlier call to the "list members on" subroutine 1208 causes. While running the "list members on" subroutine 1208 at the lowest level (ie, the highest value of the variable RS), control goes from step 1402 to step 1418 above.

In step 1418 the respective answer slot numbers are in response to that in step 1302 sent commands are attached to a field referred to herein as a member list. As a result of the tree search algorithm, values from STACK [RS] are appended from time to time until the "list members on" subroutine has reached the end of the stack at the initial level of the tree (ie, level equal to 1 and RS equal to 1). When the tree has been completely searched, the return directs from step 1420 the controller to step 1210 from 12 further.

In step 1210 brings the query subroutine 512 from 12 the controller to process 500 in step 512 back. Processing continues in step 512 to select another monitor transmit frequency to poll field MTFI as indexed by loop variable N until loop variable N exceeds value B. For each frequency, the query subroutine becomes 512 , starting in step 1201 , called for a suitable tree search. In step 1418 redundant identification numbers can be added to the list of members. As a result, step 1418 include a test that should precede attaching a transceiver identification number to the list of members if it is not already on the member list. Upon completion of the poll at each monitor transmit frequency for polling, control goes to step 514 above.

In step 514 can the contents of the list of members to the main computer 122 be reported. This reporting function can by an expression, a display, alarm, etc. in the monitoring device 124 , as discussed above, be performed (or accompanied). Further, the function of reporting identified transceiver identification numbers may be through appropriate data storage or conventional communication between the host computer 122 and / or monitoring devices 124 . 126 operational programs.

In step 516 can the host 122 and / or the monitoring device 124 initiate any command sequence, such as command 1008 for the commands discussed above 914 to 920 contains. Following the completion of all individual command / response sessions (if any), the controller enters control 518 continue where the procedure 500 starting at step 502 to repeat for continuous monitoring.

The determination of frequencies to be used for a query, discussed above, provides a list of frequencies (eg, field MTFI) prior to any polling. In an alternative method, the query may immediately proceed to detection of a response that is believed to be from a transceiver. In addition, a command / response session can be performed immediately upon discovery of a transceiver. The internal iteration loops in each of the steps 502 to 516 In such an alternative method, by appropriate controls in the main iteration loop of step 518 be replaced.

In subsequent iterations of the process 500 can the step 502 to 508 be omitted if it is expected that no additional transceivers have recently entered the communications area. Selected polling frequencies of field MTFI may be omitted if the application has not provided identification already known by using other polling frequencies. The step 512 can then be performed with a minimum of redundancy to those spent with the query To reduce time. Further, if subsequent queries do not yield new transceiver identifications, the steps may 510 to 514 be omitted and the step 516 be performed repeatedly for a list of specific transceiver identifications. For a system that monitors continued presence of transceivers without command / response sessions, the step may 512 with special (non-redundant) frequencies to receive acknowledgment from each transceiver by fully addressing the transceiver via its known complete identification. The monitoring of the presence of a known entity is generally performed in less time than the query of an unknown entity. Conversely, as an unknown set of predictably contains transceivers with identifiers in known groups (or subgroups at any level), the time spent in performing a query may be addressed and communicated with members of said known groups (or subgroups at any level). be reduced. Similarly, if it is known that a group (or subgroup) is not present (or communication with transceivers of said group or subgroup is not desired), a query may be made to ignore responses or facilitate responses from transceivers said group (or subgroup) avoids.

step 512 can be omitted for object identification systems in which only the presence of one or more objects is all that is to be monitored, for example triggering an alarm upon detection of a conveyed object. The monitoring of objects in the presence of further objects can be carried out in an alternative embodiment. For example, an alarm may be triggered upon detection of any object by a pass unless it is accompanied by detection of another predetermined object (e.g., a transceiver in an authorized person's trailer).

step 508 can be omitted when step 506 provides sufficient resolution of one or more frequencies.

One Method for improving the reception of a response signal during a Query or data communication includes the steps: (a) Send a carrier signal on a first frequency; (b) sampling a response signal, (c) Identify one or more frequency components who were not expected to be part of a real one Response signal is / are; and (d) programming a filter to dampen said one Frequency component (s). The transmitted carrier may be at a tank resonance frequency, a Stacking frequency or one for use with one loose with a stack coupled tank circuit suitable frequency. Sampling and identification of frequency components can be done in done in any way Be that as well discussed above Includes time domain signal processing and / or frequency domain signal processing. Of the Filter can be a digital filter, a programmable element network or include a programmable active filter. The filter characteristic can be a low-pass, bandpass, Notch, comb or high pass transfer function contain. Sending and sampling can be done during a reply slot respectively.

One Method for improving the accuracy of a query scenario contains the steps: (a) determining a first series of amplitude sample points a response signal; (b) comparing the first row with a second row of for a resonant circuit response expected amplitude values; and (c) continue in the log of the query scenario in accordance with whether the Scope of the comparison has exceeded a threshold.

A transceiver according to various aspects of the present invention includes any circuit for performing the above with reference to FIG 8th discussed process. For example, one may be used to perform the instruction set of 10 using the message formats of 11 capable transceiver 201 Receive and send data using a combination of Off / On Keying (OOK) and duty cycle modulation.

The functions of the rectifier 206 , Recipient 208 , Transmitter 210 and the state machine 212 may be based on a description of the timing of in the transceiver 201 used signals are better understood. During a polling scenario, multiple messages may be received by a transceiver. Any message awaiting response from any transceiver forms a request. An interrogation scenario may contain multiple requests. For example 15 the signal TANK is as if it were via lines 217 and 219 (ie the difference of the signals N1 and N2) appear. Portions of the TANK signal match portions of a query format 1500 match the starting section 1593 , Head section 1594 , Message type section 1595 , News section 1596 and answer slot section 1597 contains. The signal TANK is from the rectifier 206 rectified to a Gleichspan V + to supply, which is used to all circuits of the transceiver 201 to provide energy. The signal TANK is received by the receiver 208 demodulates to a signal DEMOD on the line 214 provide. In addition, the signal TANK by overlay contains the output of the transmitter 210 in response to modulating signal MOD on the line 216 , From time T1502 to time T1504, the transceiver receives 201 an unmodulated carrier on the TANK signal. The time period from time T1502 to time T1504 sets forth above with reference to the process 802 discussed START signal 1593 The duration of the START signal should be sufficient for the rectifier circuit 206 to provide continuous energy to the transceiver 201 for the operating time required by the polling protocol.

Following the START signal, the TANK signal has a number of periods of 50% duty cycle modulation sufficient to produce proper timing signals for use in the transceiver circuit 201 , For example, the signal CELL CLK from the signal DEMOD on the line 214 derived and the signal RX CLK derived such that it has active edges in the midpoint between the active edges of the signal CELL CLK. The signal CELL CLK represents a cell clock which, by its active edges, marks the falling edge of each cell used for communication of a data bit. From time T1504 to time T1506, no carrier is received. From time T1506 to time T1510, a carrier is received. This sub-sample sample will be for the entire header 1594 until time T1516. The length of the head section 1594 should be used to generate all the timing signals for use in the transceiver circuit 201 suffice.

The received clock signal RX CLK has an active edge in the middle of each data communication cell for discriminating between cells transmitting a logical "0" and cells containing a logic "1". The cell content clocked by signal RX CLK is represented as signal RXD, which is a "010" pattern for the message type portion 1595 transmitted.

The logical "0" of the signal RXD is derived from a cell, the modulation in only the latter Contains section of cell duration. For example, no carrier becomes received from time T1516 to time T1520; however, one will carrier from time T1520 to time T1522. The duration of Time T1520 at time T1522, divided by the cell duration (from time T1516 to time T1522) represents a work cycle from 10% to 45%, preferably 40%. The active edge of the signal RX CLK occurs while the signal DEMOD is low at time T1518, from which the signal RXD is determined to be a logical "0". in the Contrast contains the next Cell starting at time T1522 and at time T1530 extending a section from time T1522 to time T1524, in which no carrier is received, and a section from time T1524 to time T1530, while its a carrier Will be received. The duration from time T1524 to time T1530 divided by the cell duration (from time T1522 to time T1530) provides a duty cycle (unlike the duty cycle the cell from T1516 to T1522) from 55% to 90%, preferably 60% The active edge of the signal RX CLK occurs while the signal DEMOD is high at time T1526, from which the signal RXD as a logical "1" is determined. The following Cell extends from time T1534 and has another one logical "0".

The message type section 1595 the query format 1500 extends from time T1516 to time T1534. Following the message type section 1595 extends the news section 1596 from time T1534 to time T1550. During the news section 1596 transmit the signal TANK and signal DEMOD data using interrupt keying modulation, preferably with 40% and 60% duty cycle modulation. In one variant, each bit of the message type section becomes 1595 are sent as two complementary bits in sequence (e.g., a dibit) to facilitate a form of redundancy for message validation testing. Similarly, command and / or argument portions of each message format 1100 . 1110 . 1120 . 1130 or 1140 be sent as dibits.

The signal CELL CLK and signal RX CLK settle on the message section 1596 (not shown for clarity). From time T1550 to time T1580 will be response slots 1597 distinguished by the signal TANK. reply slots 1597 contain one answer slot for each answer. The duration of a reply slot is equal to one period of the CELL CLK signal. For example, from time T1550 to time T1554, no carrier is received; however, a carrier is received from time T1554 to time T1558. The signal received from time T1554 to time T1558 (and analog times in other reply slots) performs several functions, including: maintaining power supplied by the rectifier circuit, marking a boundary between adjacent reply slots, defining a duration (e.g. one cell clock period) for synchronizing other clock signals (eg, an 8-times cell clock frequency signal), identifying the beginning of an offset in the answer slot for signal detection (eg placement of the active edge of the signal RCV CLK) and identification of the beginning of an offset in the response slot for transmission of a response signal. By marking the boundary of a response slot with a carrier for a predetermined portion of the CELL CLK signal (e.g., 10% to 90%, preferably 40% to 60%, most preferably about 50%), the CELL CLK signal may be at boundaries of all Response slots remain synchronized. In an alternative embodiment where transmission of energy during response slots is not required, the signal CELL CLK may be coupled to the header 1594 be synchronized and the monitoring device 124 while answer slots 1597 send nothing.

During the response slot from time T1550 to time T1558, no response is displayed. The response slot from time T1558 to time T1566, however, contains a response during the portion of the slot where the signal MOD indicates that the transmitter 210 provides a modulation. The signal MOD activates a transmission from time T1560 to time T1562, that is, during a time when no carrier from the monitoring device 124 provided. As with reference to 16 explained in more detail, the duration of the signal MOD overlaps a portion of that of the monitoring device 124 sent carrier.

Any number of answer slots may be used. If 1000 Response slots are defined, signals can have the durations described in Table 4. The signals in Table 4 are consistent with a message format 1140 match, which is immediately a message format 1130 followed. The reply slot used to respond to this series of message formats is the answer slot associated with the command and argument sections immediately preceding the answer slot section, regardless of the number of previous message formats. Of course, the same argument values can be used redundantly to ensure proper reception. In this example, the argument 1142 same as argument 1132 be.

TABLE 4

The timing diagram of 16 FIG. 12 illustrates the use of additional clock signals for deriving the signal RX CLK and the signal MOD. The signal TANK is shown in a cell which is comprised of a first portion from time T1602 to time T1610 where no carrier is received and a second portion of Time T1610 to time T1616, where a continuous carrier is received. The signal DEMOD is represented with a transmission corresponding to a 50% duty cycle modulation. Signal RX CLK provides an active edge (in the middle of the cell) corresponding to the rising edge of the illustrated signal DEMOD. The DEMOD signal, if transmitting a logic "1", would have a rising edge at time T1608 that provides sufficient preprocessing time before the active edge of the RX CLK signal. When the signal DEMOD transmits a logic "0", the rising edge of the signal DEMOD is delayed until time T1614, providing sufficient hold time following the active edge of the signal RX CLK.

The signal MOD may be formed from signal Q2 from time T1606 to time T1610. Preferably, the duration of the signal MOD extends over the time 1610 out so that from the transmitter 210 Modulation provided the transmission of a carrier from the monitoring device 124 overlaps. By overlapping the transmission of signals by the monitoring device 124 and the transmitter 210 becomes the transmitter 240 in a neighboring transceiver is unlikely to confuse a modulation shortage between the falling edge of the signal MOD, for example, at time T1610 with the boundary of the cell occurring at time T1616. In this way, each transceiver can accurately detect a cell boundary by the falling edge of the DEMOD signal and maintain synchronism of clock signals including the CELL CLK signal.

The signal REPLY of 16 represents the portion of the TANK signal that would be superimposed on the TANK signal when the transceiver 201 sends a response in response to the signal MOD. From time T1606 to time T1612, the amplitude of the signal REPLY depends on the Q of the tank circuit 204 and the power available for transmission. From time T1606 to time T1609, the amplitude largely depends on Q. From time T1609 to time T1612, the amplitude decreases as the power available for transmission decreases (although sufficient energy can remain for logic functions).

The transceiver 201 can be constructed on a substrate as an integrated circuit. The cost of manufacturing an integrated circuit for a circuit of limited complexity (eg, transceivers 201 ) are adversely affected by the area of the substrate intended for pads for connecting the integrated circuit to external devices. A preferred set of pads for integrated circuit interface signals is described in Table 5. Using conventional voltage selection or alternate mode control circuitry, pads may be used for multiple signals and additional pads may be omitted. For example, pad can 2 also be used for signal FUSE PROG; Can pad 6 also be used for signal FUSE DATA; and can pad 7 also be used for signal FUSE CLK.

TABLE 5

The rectifier circuit 206 may include any conventional circuit for developing a DC voltage from a received carrier signal. For example, the rectifier contains 206 from 17 a bridge rectifier 1700 over the wires 217 and 219 , an energy storage capacitor C1710, a series regulation circuit 1712 and a circuit 1716 to determine when the developed voltage is of sufficient magnitude for transceiver operation. The rectifier circuit 1700 includes diodes D1702, D1704, D1706, and D1708 in a conventional full-wave bridge arrangement. The tank circuit 204 (containing antenna 202 and capacitor 1703 ) is over the middle of the bridge 1700 connected. A full-wave rectified capacitance signal FRC on line 1718 can be transported to an external connection for additional capacity to earth. The control circuit 1712 receives the signal FRC on the line 1718 and provides in a conventional manner a signal V + with a suitable voltage magnitude on a line 1717 , A comparator 1716 compares the signal V + on the line 1717 with the output of a conventional voltage reference circuit 1714 (eg, a bandgap reference circuit, zener diode, etc.). The comparator 1716 provides a signal VOK when the voltage on the line 1717 the output of the voltage reference 1714 exceeds. The signal VOK activates a transceiver operation. The rectifier circuit 206 can receive sufficient power for transceiver operation when the monitoring device 124 on the resonant frequency of the tank 206 which transmits the stack resonance frequency discussed above, or any frequency and any energy level, that of the transfer function of the tank 206 (including antenna 202 ).

The recipient 208 may include any conventional receiving circuit. Special advantages are in the system 100 through the receiving circuit 208 from 18 scored that a detector 1808 , a flip-flop 1812 , a phase locked loop 1814 and a gate logic 1824 contains. receiver 208 can be at the resonant frequency of the tank 206 operated at the stack resonance frequency discussed above, or any frequency and any energy level, that of the transfer function of the tank 206 (including antenna 202 ).

The detector 1801 includes a full-wave rectifier, a filter and a Schmitt trigger inverter. A signal N1 on line 217 passes through diode D1802 to line 1809 and is shunted by filter capacitor C1806 and filter resistor R1808. Similarly, signal N2 goes on line 219 through diode 1804 and turn it on line 1809 , The administration 1809 provides a signal through the shunt filter to the Schmitt trigger inverter 1810 , The inverter 1810 provides a signal DEMOD on line 1823 , The signal DEMOD clocks T-flip-flop 1812 to get a 50% duty cycle signal on line 1811 to deliver.

The phase locked loop 1814 contains a phase frequency detector 1816 Voltage Controlled Oscillator (VCO) 1818 and a counter 1820 , The VCO 1818 works at 160 KHz to provide a VCQ oscillating signal on line 1819 to deliver. The signal VCQ is from the counter 1820 divided to deliver 80KHz, 40KHz, 20KHz and 10KHz. The 50% duty cycle signal on line 1811 gets on line with the 10 KHz signal CELL CLK 1821 from the phase frequency detector 1818 compared to a voltage control signal VXC on line 1817 to deliver.

A gate logic 1824 provides signals RX CLK on line 1827 and signal TX GATE on line 1829 in a conventional manner according to the timing diagram of 16 ,

The recipient 208 may, in an alternative configuration, be a detector 1902 from 19 instead of the detector 1801 contain. The detector 1902 contains an inverter 1904 , a switching transistor 1905 and a filter with capacitor C1906 and resistor R1908. The inverter 1904 receives a signal FRC on line 1718 from the rectifier 206 , The switching transistor 1905 interacts with the capacitor C1906 in a manner similar to a charge pump (eg, an integrator) to supply the signal DEMOD on line 1823 to deliver.

The transmitter 210 can be any conventional transmission circuit. Special advantages are in the system 100 using a transmission circuit of 20 scored that an analog switch 2002 , Amplifier 2006 and a tank circuit 204 contains. The tank circuit 204 forms the only resonant circuit in the transmitter 210 , The tank circuit 204 thus governs the frequency of the transmitter 210 , Any magnetic coupling in the antenna 202 can change the resonant frequency of the tank 204 influence and thus that of the transmitter 210 influence the transmission frequency provided. The transmitter 210 can contain either a Colpitts or Hartley oscillator design. For example, the sender contains 210 from 20 a capacitor C2004, amplifier 2006 , Capacitor C2008 and bridge capacitors C2010 and C2012. The bridge capacitors together correspond to the capacitance C1703 described above. Capacitors C2004 and C2008 provide AC coupling and DC blocking in a conventional manner. The analog switch 2002 receives the signal MOD on line 216 , When the MOD signal is registered, a feedback signal on line becomes 219 with the amplifier 2006 coupled to complete the controlled oscillator.

In an alternative transmitter, the frequency to be transmitted is determined in part by the previously received frequency. For example, the sender contains 210 from 21 a phase locked loop 2100 and a disconnecting circuit 2112 , The phase locked loop 2110 contains a phase frequency detector 2102 , a holding circuit 2106 and a voltage controlled oscillator 2110 , The VCO 2110 works on 5 MHz to signal a OSC on line 2111 to the phase frequency detector 2102 to deliver. A signal N1 on line 217 is also with the phase frequency detector 2102 coupled. The phase frequency detector 2102 responds to a phase difference between the signal N1 and signal OSC to a signal VJ on line 2103 to deliver. The holding circuit 2106 responds to a signal DEMOD on line 1823 by holding the value of the signal VJ when the signal N1 is not received. The holding circuit 2106 provides a signal VK on line 2107 for controlling the oscillator frequency of the VCO 2110 ,

Response frequencies for above with reference to the 20 and 21 Transmitters discussed are described in Table 6. The transmitter of 21 is preferred for stacked embodiments.

TABLE 6

By sampling the received signal N1 while a carrier is being transmitted by the monitoring device 124 and maintaining the received frequency for generating the frequency to be used for transmission, the transmitter provides 210 from 21 a transmit signal at a frequency better for communication with the monitor 124 suitable is. The transmitter 210 may be one of the monitoring device 124 specified transmission frequency as opposed to one from the tank 204 have certain frequency. The operation of the transmitter discussed above 210 is for objects 107 and 112 , each one at one end of the stack 116 are particularly advantageous. Although the resonant frequency of the coupled tanks of the objects 108 to 111 from the monitoring device 124 can be detected for the purpose of providing sufficient energy and accurate data communication at a particular selected carrier frequency, the same carrier frequency can not sufficiently dissipate energy into objects 107 and 112 Coupling or provide reliable communication due to the weaker coupling, for example, between the tank circuits of the objects 107 and 108 as far as the tank circle of object 107 not similar between two others is located.

The state machine 212 may include any conventional condition machine circuit for performing the functions described above. For example, the state machine 212 in the 22 described circuit containing a synchronization logic 2204 , a shift register 2202 , a latch 2206 , a comparator 2208 , an access state logic 2210 , a store 2214 and a counter 2224 contains. These building blocks act to provide the query commands described above 1004 to 1007 together. Additional logic may be used to access state logic 2210 be added to commands 1000 to 1003 using conventional techniques. The state machine 2102 can be extended to a command 1008 to perform the commands discussed above 914 to 920 equivalent. In such an extended configuration, the state machine also includes a multiplexer 2212 , a sensor 2216 , an analog-to-digital converter 2218 , a multiplexer 2220 , a multiplexer 2222 , a shift register 2240 and a multiplexer 2228 ,

The shift register 2202 receives a signal DEMOD on line 1823 that is from signal RX CLK on line 1827 is clocked. The contents of the shift register 2202 is considered a valid message if the message type section 1595 the parallel data output of the shift register 2202 matches a predetermined message type code. As in 15 For example, type "010" can be used for signal RXD starting at time T1518. Type "010" is used herein for all above with reference to FIGS 10 used commands described. Other message type codes may be used; or additional message type codes may be used in an extended set of commands, as discussed above with reference to FIG 9 discussed. The shift register 2202 delivers in parallel data format 2203 the message type code, an access code, and a corresponding level code. The message type code becomes the synchronization logic 2204 made available. The access code (eg argument 1132 from the message format 1130 ) becomes the comparator 2208 made available. The layer code (for example, command 1131 from the message format 1130 ) is the latch 2206 , the access state logic 2210 , the multiplexer 2212 and multiplexers 2220 made available. The shift register 2202 may include a holding register for holding the output codes for processing until a subsequently received message has completely arrived. A subsequent message is considered complete when a valid message type code is a START signal 1593 and head 1594 follows, as in 15 shown.

A signal discriminator includes any circuit that derives mode control signals (e.g., message type, load, preset, etc.) and timing signals (eg, reset and clocks) from a composite signal. For example, the receiver works 208 with the synchronization logic 2204 to provide a discriminator that derives signals from received messages. For example, the receiver routes 208 the signal CELL CLK on line 1821 and receives the Synchronsierlogik 2204 a message type code on bus 2203 from the shift register 2202 and receives it a signal CELL CLK on line 1812 and provides numerous reset signals. The synchronization logic 2204 In addition, other clock signals with higher frequency than the signal CELL CLK on line 1821 receive and generate. The synchronization logic 2204 generates, inter alia, the initial states for Latch 2206 , Access state logic 2210 and counters 2224 , The synchronization logic 2204 detects an operating condition and generates initial conditions in response thereto. The synchronization logic 2204 clears latch 2206 and clears all access state bits B0-B3 in access state logic 2210 using the signal SRST on line 2233 , The synchronization logic 2204 provides a signal CRST on line 2201 to clear the counter 2224 as an initial state. The synchronization logic 2204 also supplies a signal CEN to a comparator 2208 for activating a comparison at a time determined, for example, from time T1516 to the beginning of the message type section 1595 one in 15 match the query format shown. Time T1516 can be determined based on a predetermined number of active edges on signal CELL CLK according to a suitable protocol.

The latch 2206 contains an addressable access state flip-flop for each access state bit B0-B3. A signal LEVEL is used as an address for selecting a flip-flop to be set. A selected flip-flop is by interaction of the signal CEN on line 2231 and signal D on line 2235 set. The leading edge of the signal CEN provides a clock and the signal D generates the state of the addressed flip-flop. The signal D is on line 2235 from the access state logic 2210 provided in accordance with: (a) that of the latch 2206 on line 2207 provided access state, and (b) the signal LEVEL on line 2203 , By allowing the access state logic to determine signal D under many conditions, the addressed flip-flop in the latch 2206 as above with reference to the commands 1004 to 1007 be discussed, adjusted or left unaffected, as for the commands discussed above 1000 to 1003 , The latch 2206 Returns the output of each flip-flop as the ACCESS STATE signal on line 2207 to the address state logic 2210 ,

The access state logic 2210 receives the signal ACCESS STATE on line 2207 from Latch 2206 and receives the signal LEVEL on line 2203 from the shift register 2202 , Based on these inputs, the access state logic 2210 a spare memory address signal on line 2209 with suitable control signals 2211 deliver to a selection through multiplexer 2212 from a suitable address on line 2217 to cause the retrieval of an access code from memory 2214 to use. In an alternative embodiment, the LEVEL signal is used directly as a memory address for the memory 2214 is used, the multiplexer 2212 with appropriate simplifications to the access state logic 2210 be omitted. In such an embodiment, the address input 2217 of the memory 2214 from the shift register 2202 on the bus 2203 supplied to provide the signal LEVEL as the address. The access state logic 2210 provides a read-write control for the memory 2214 on line 2213 as signal R / W. The access state logic 2210 also provides control signals 2211 to the multiplexer 2222 to select data on the bus 2225 as a signal to deliver MDATA.

The multiplexer 2222 put a bus 2225 for the comparator 2208 , Counter 2224 and the shift register 2240 ready. The signal MDATA transmits a stored access code to the comparator 2208 or memory contents or sensor data to the counter 2222 and the shift register 2240 ,

When activated by signal CEN on line 2231 supplies the comparator 2208 Comparison results on signals 2205 to the access state logic 2210 , If, for example, an access code on bus 2203 with a stored memory 2214 on bus 2225 provided access code exactly matches, becomes an A = B output of the comparator 2208 logged in and to the access state logic 2210 delivered. When the signal CEN activates a comparison and the access code on line 2203 not exactly the same as the access code on the bus 2225 is, is by the comparator 2208 an A ≠ B output logged in and to the access state logic 2210 delivered. In a preferred configuration, the access state logic responds 2210 to an A ≠ B signal with driving the signal SRST on line 2233 to thereby the latch 2206 reset to its initial state and the synchronization logic 2204 to inform to provide any further reset or initial conditions, as appropriate. Regardless of the sequence in which the multiple multiple-level access codes are presented for comparison, the state machine returns 212 in fact, if any such access code is not exactly equal to that from memory 2214 retrieved corresponding access code, returns to its initial state and waits for a subsequent START signal. As a result, an addressed transceiver will enter a reset state (and may enter an off state) to avoid transmission if it is not properly addressed at a subsequent level. The of the access state logic 2210 provided control signals 2211 control all aspects of the operation of the state machine 212 in a conventional manner. Such a control signal, signal OS on line 2215 , indicates the multiplexer 2228 to provide a signal MOD in accordance with the issue selection signal OS as discussed below.

The memory 2214 may include any conventional data storage technology or multiple such technologies in any combination. The memory 2214 may be organized to store memory contents on line 2223 , as shown, in parallel format or in serial format in an alternative architecture. In such an alternative architecture, the state machine 212 a serial comparator instead of the parallel comparator 2208 contain. The memory 2214 delivers on wire 2223 a 10-bit access code in parallel with a 10-bit reply slot number. The answer slot number can be over the multiplexer 2222 transferred and into the counter 2224 getting charged. The memory 2214 provides for storing any number of (access code, answer slot) pairs. In a preferred embodiment, 4 such pairs provide unique transceiver identification, and 4 additional pairs provide alternative identification or support for alternative query protocols. For example, the commands can 1000 to 1003 have different respective argument values, one for each instruction. The one in the command 1004 used GID can with the in the command 1000 GID used to be identical. These four GID "standard" values can be used in many (eg all) transceivers for use in a particular installation of the system 100 get saved. The knowledge of one or more of these four "standard" GID values by the monitoring device 124 (or host 122 ) facilitates querying in any sequence of instructions 1004 - 1007 if requirements are not used or modified accordingly.

When clocked by signal CELL CLK on line 1821 delivers the counter 2224 a signal ZM on line 2227 if the answer slot number is reduced to zero.

The multiplexer 2228 provides a signal MOD on line 216 in response to the AND combination of the TX GAT signal on line 1829 and signal ZM on line 2227 to activate sending a response confirmation in the reply slot associated with the access code that is simultaneously on the memory output line 2223 provided.

To support commands of the in 9 described type, for example commands 914 to 920 , for example, command 1008 from 10 , can the state machine 212 any or all contents of the memory 2214 in the shift register 2240 by suitable operation of the multiplexer 2222 through the access state logic 2210 via control signals 2211 load. When loaded as described above, the shift register responds 2240 on the signal CELL CLK on line 1821 as activated by counter 2224 Output on line 2231 to send a signal QM on line 2229 provide.

The access state logic 2210 can a signal OS on line 2215 to the multiplexer 2228 to provide three response message formats. When the signal OS a multiplexer input A on line 2227 First, the correct timing for a response in a prescribed reply slot (e.g., answer slots 1125 or 1135 ) from the signal MOD on line 216 provided. When the signal OS on line 2215 is logged in order to activate a multiplexer input B determines the signal QM on line 2229 in AND combination with signal TX GATE on line 1829 the state of the modulation signal MOD on line 216 , The signal MOD on line 216 consequently transmits the contents of the shift register 2240 sequentially. The counter 2224 can in conjunction with the shift register 2240 operate using conventional logic for one of two functions: (a) provide a fixed number of bits from the shift register 2240 in turn on lead 216 as a signal MOD in a second response message format (eg, response bits 2214 ); or (b) provide one bit from the shift register 2240 in every occurrence of answer slot section 1597 until the entire contents of the shift register 2240 in a manner corresponding to conventional time domain multiplexing in a third response message format (e.g., answer slots 1125 or 1135 ) has been provided.

The sensor 2216 represents any electronic transducer, the sensors of the above with reference to the sensors 160 and 162 contains described type. The sensor 2216 provides an analog signal to the analog-to-digital converter (ADC) 2218 , The ADC 2218 provides a sensor data signal SDATA on lines 2219 to the multiplexer 2220 , The multiplexer 2220 that of control signals 2211 is operated, allows selection of either a received data signal RDATA on bus 2203 from the shift register 2202 or a sensor data signal SDATA on line 2219 that either: (a) in the memory 2214 over bus 2221 to save; or (b) via the multiplexer 2222 either to the counter 2224 or the shift register 2240 to deliver. When delivered to the meter 2224 For example, sensor data, for example a 10-bit value, may act as a response slot number as described above for providing a response signal in a response slot. When delivered to the shift register 2240 may select data for providing the signal MOD on the line 216 in any of the response message formats described above.

The received data signal RDATA provides, when forming the modulation signal MOD on line 216 is used for the ability of a transceiver to return data as received to perform a test of a single transceiver. Tests may include (a) testing data communication reliability in a laboratory environment; and (b) testing transceiver reliability in the presence of external factors, including, for example, variation of the device environment, varying the strength and frequency of sources of interference, and varying the number and proximity of similar transceivers in a laboratory or installation environment.

In response to a suitable command, the access state logic 2210 a write by signing a signal R / W on line 2213 at memory 2214 call. Data to be written to the memory may be from the shift register 2202 as signal RDATA on bus 2203 over the multiplexer 2220 be provided or from the sensor 2216 over the multiplexer 2220 to be provided. Data written to the memory may include original (or revised) access code and slot number for one or more values of the LEVEL signal. The write memory operations may be used to facilitate the code hopping discussed above.

Parts of the state machine 212 can help reduce energy consumption, reduce the cost of manufacturing a transceiver 201 or omitted if one or more functions for an installation of the system 100 is not desired / are. For example, the sensor 2216 , the ADC 2118 and the multiplexer 2220 be omitted if the transceivers are not used to measure the one tran sceiver surrounding environment. In addition, the multiplexer 2222 omitted if test functions described above are not desired. The shift register 2240 and the multiplexer 2228 can be omitted if the message format 1130 or 1120 is sufficient for an answer and the message format 1110 not wanted. The memory 2214 may be read-only, in which case the signal R / W on line 2213 with concomitant simplifications to the access state logic 2210 can be omitted.

The memory 2214 may include a random access memory organized as conventional Random Access Memory (RAM) or as a shift register memory. Also, the read-only areas of the memory can be 2214 contain any combination of ROM, PROM, EPROM, E ² PROM and fuse programmable memory.

Special benefits are in the transceiver 201 by using a circuit for a fuse-programmable memory. For example, circuit contains 2300 from 23 a shift register 2302 , a decoder 2304 and a field of programmable fuses by a programmable fuse circuit 2314 and a tri-state driver 2316 are exemplified, for each memory bit. The circuit 2300 takes on lead 2310 a serial signal FUSE DATA, which transmits binary data to be stored in the memory. The shift register 2302 is from the signal FUSE CLK 2312 clocked until all data to be stored in the memory has been received. When signal FUSE PROG is signaled on line 2315 each fuse element in the respective fuse circuit 2313 simultaneously according to the parallel output of the shift register 2303 programmed. The fuse element in the fuse circuit 2314 may be any conventional fuse element, diode, zener diode, polysilicon fuse or metal element. After programming can be any group of programmed fuses 2322 on bus 2223 be logged when a signal ADDR on line 2217 the decoder 2304 to trigger a suitable tri-state buffer enable signal, for example, as on line 2327 to deliver. The activation signal on line 2327 activates tri-state buffers 2324 for providing memory output data to bus 2223 as signal Q. The fuse circuits 2314 may be grouped in any suitable manner to form any number of data output bytes or words in response to corresponding addresses defined for the signal ADDR.

To the Sending enough energy in a reply slot is mainly done by during that received carrier of a START section of the message format received. If a transceiver does not have more than one response per START signal returns, the REPLY signal may go off during drop off. A quick fall ensures that the Does not continue sending in a subsequent reply slot; facilitated the application of maximum energy during transmission before the start the waste; and allows a consumption of energy during the To inevitably result in a complete reset of the access state respectively (eg if the VOK signal is no longer logged in).

In an embodiment with battery power for Transceiver circuits can the advantageous operating features discussed in the preceding paragraph by transferring (for one limited duration) of energy from the battery to a capacitor which, as discussed above, provides limited energy.

The monitoring device 124 may include any computer-controlled transceiver for conducting an appropriate polling protocol and communications, as discussed above. In addition, a monitoring device with numerous sensors 160 work together, numerous controls 164 deliver and with numerous as an antenna system 120 organized antennas work together. As in the functional block diagram of 24 shown contains the monitoring device 124 for example, a central processing unit (CPU) 2402 , a store 2404 and a conventional data communication bus 2406 , The data bus 2406 couples the CPU 2402 and the memory 2404 for the conventional execution of stored programs in memory 2404 from the CPU 2402 , The bus 2406 additionally provides data communication between the CPU 2402 and functional blocks containing: computer network control 2408 , Event detectors 2410 , Output registers 2411 , Antenna network control 2412 , Receiver 2416 and 2418 , digital signal processor (DSP) 2420 , Transmitter 2424 and 2426 and programmable frequency source (PFS) 2422 , The transmitters 2424 and 2426 deliver transmitted signals to a coupler 2414 ; and the coupler 2414 provides received radio frequency signals to the receivers 2416 and 2418 , By providing two functionally equivalent receivers and two functionally equivalent transmitters in common with a coupler, the monitoring device can 124 Simultaneously transmit on two frequencies and receive simultaneously on two further independent bands. For this purpose, the PFS delivers 2422 a signal "Programmable Frequency Source Output (PFSO)" on line 2423 to every station 2424 and 2426 , The signal PFSO can be provided to each transmitter on separate lines at different frequencies. The transmitters 2416 and 2418 , each having a respective signal RF on line 2417 and a signal RFN on line 2419 receive samples of received signals in digital format on a bus 2421 to the DSP 2420 deliver. The CPU 2402 can the DSP 2420 Control to Arrange: (a) Operation with one or both receivers 2416 and 2418 ; (b) a timing for starting the processing of sampling points of bus 2421 ; (c) a sampling period; (d) configuration parameters for selecting a method for digital signal processing; (e) a procedure and format in which the DSP 2420 Delivers results; and (f) the destination for the results, ie, whether to the CPU 2402 , to the store 2404 , for further processing by the CPU 2402 or to the computer network controller 2408 for a transfer to the main computer 122 ,

DSP 2420 may perform digital signal processing including amplitude averaging, energy calculation, digital filtering, peak detection, time domain edge enhancement, phase analysis, frequency analysis, transformation (eg, fast Fourier transform), correlation, superposition, curve fitting, and energy spectral density calculation.

The memory 2404 provides storage for programs and data, mainly from the CPU 2402 and the DSP 2420 be used. The memory 2404 may include data structures, arrays, stacks and combinations thereof for storing signal features discussed above. The memory 2404 (or host 122 ) may also contain group identification and subgroup identification hints (for each level) for use in query scenarios. These cues may be for use in other independent embodiments of the system 100 exclude reserved access codes (or not included). For example, access code ranges may be specified algorithmically or as one or more lists in which not all access code values or combinations of values are made available for use during the query.

The computer network control 2408 may be any conventional interface for coupling the data bus 2406 with the main computer 122 contain. For example, the computer network controller 2408 contain a conventional Ethernet interface. One from the computer network controller 2408 provided bus 128 may be consistent with any computer network standards, for example, any telecommunications network standards or standard used in communications over the Internet or the World Wide Web. The computer network control 2408 may include one or more additional processors for managing, for example, a TCP / IP stack or performing any suitable protocol. The computer network control 2408 (and / or the CPU 2402 ) can with the host 122 communicate using a command language described in Table 7. Each command contains an ASCII character to identify the command followed by argument values. Operating frequencies can be identified in numerous command / response sessions by integers called bins. For example, a working range from 1.9 MHz to 8.038 MHz can be divided into 1024 bins, where the frequency corresponding to a particular bin-integer is calculated using the expression: F (bin) = bin * 6 KHz + 1900 KHz.

TABLE 7

The recipients 2416 and 2418 can be any conventional receiver. Special advantages are in the system 100 by using a receiver circuit 2416 from 25 get that a preamp 2502 , a diode detector 2504 , a synchronous detector 2506 , an analog switch 2508 , Filters 2510 , an ADC 2512 , a first-in-first-out (FIFO) register 2514 and control registers 2526 contains. The preamp 2502 receives a signal FR on line 2417 and provides gain and automatic gain control (AGC). The gain and frequency response characteristics of the preamplifier 2502 be in a conventional manner of signals 2509 of control registers 2526 as of CPU 2402 specified, prescribed. The preamp 2502 provides a signal RFW on line 2503 to one or more detectors.

The diode detector 2504 receives a signal RFW on line 2503 and provides a demodulated signal DX on line 2505 , Any conventional diode detector may be used. The diode detector 2504 preferably represents a broadband detector for detecting transceivers in a stack, especially transceivers with a transmitter of the type described with reference to FIG 20 described type. Special advantages in the system 100 be by using the diode detector 2504 from 26 receive.

The synchronous detector 2506 receives a signal RFW on line 2503 and provides a demodulated signal SX on line 2507 , Any synchronous detector circuit may be used to provide the demodulating function, including, for example, a conventional tracking filter circuit. The synchronous detector 2506 represents a narrow band detector.

The analog switch 2508 dials under the direction of control registers 2526 one or more detector output signals, for example signal DX on line 2505 and / or signal SX on line 2507 and provides a demodulated signal (eg, an overlay) to filters 2510 ,

The filters 2510 may have any filter transfer functions (e.g., lowpass, bandpass, highpass, and notch), as by signals on line 2511 from the CPU 2402 instructed control registers 2526 instructed to implement. The output of the filters 2510 is from the ADC 2512 converted to digital sampling points. Said sampling points are in the FIFO 2514 saved and sent to the CPU 2402 and / or the DSP 2420 delivered. The ADC 2512 may include any conventional analog-to-digital converter circuit. Upon receiving a 5 MHz response or a 5 MHz response signal, sample points 417 at 40 MHz to provide sufficient resolution for signal analysis, as discussed above. In an alternative embodiment of the receiver 2416 is the signal RFW with the ADC 2512 coupled and become detection and filtering of CPU 2402 , DSP 2420 or from the main computer 122 under the use of for example, conventional digital technologies are performed.

The diode detector 2504 from 26 contains an inverting amplifier 2602 , a non-inverting amplifier 2604 , Transistors Q2606 and Q2608, a capacitor C2610, a resistor R2612 and output buffer 2614 , The amplifiers 2602 and 2604 receive a signal RFW on line 2503 and provide base drive signals to transistors Q2606 and Q2608. Transistors Q2606 and Q2608 rectify the radio frequency content of signal RFW. Capacitor C2610 and resistor R2612 act as a filter to receive rectified signals from transistors Q2606 and Q2608 and provide the filtered waveform to the output buffer 2614 , The output buffer 2614 provides a signal DX on line 2505 in a conventional manner.

Special advantages are in the system 100 by using a synchronous detector from the in 27 achieved type described. The synchronous detector 2506 from 27 contains an inverting amplifier 2702 , a non-inverting amplifier 2704 , an analog switch 2706 , a filter 2708 and a programmable oscillator 2710 , The amplifiers 2702 and 2704 receive a signal RFW on line 2503 and provide buffered signals to the analog switch 2706 ,

The analog switch 2706 selects the output of the amplifier 2702 for the output of amplifier 2704 under the direction of the signal SC on line 2705 from the programmable oscillator 2710 out. The programmable oscillator 2710 works on a frequency, phase and duty cycle, prescribed by the CPU 2402 through tax registers 2526 and receive on line 2501 from the programmable oscillator 2710 , The phase can be detected relative to zero crossings in a conventional manner from the signal RFW. The programmable oscillator 2710 For example, a conventional synchronizing circuit may receive the signal RFW and provide the signal SC in a phase relationship with the signal RFW, such as signals from control registers 2526 Guided, included. The output of the analog switch 2706 may include harmonics of the switching frequency of the signal SC. The filter 2708 receives the output of the analog switch 2706 and attenuates unwanted frequency components. The filter 2708 may include any conventional filter circuit, for example, lowpass, notch, bandpass, comb, etc. The filter 2708 provides a signal SX on line 2507 ,

The recipients 2416 and 2418 can each be operated with a synchronous (narrow band) detector. The received signals may be received or delayed on one or more suitable antennas to provide a 90 ° phase difference between otherwise identical signals prior to detection. When a synchronous detector is operated at the same frequency as the other but with a 90 ° phase shift in the clock signal SC, the detected amplitudes correspond to conventional I and Q signals for phase detection and phase-based signal analysis, as discussed above.

The transmitters 2424 and 2426 may include any conventional transmission circuit. Special advantages are in the system 100 using a transmission circuit 2424 from 28 scored a shift register 2802 , a counter 2804 , a multiplexer 2806 , a duty cycle modulator 2808 , a control logic 2812 and an output gate 2810 contains. The data bus 2406 from CPU 2402 provides the transmitter 2424 with information to be sent and configuration parameters for the control logic 2812 , Information to be sent is in the shift register 2802 according to the control logic 2812 provided suitable control signals 2830 loaded. The contents of the shift register 2802 can refer to above with reference 11 and 15 match the message formats described. In both cases, the answer slot portion of the message formats 1120 and 1130 by operation of the counter 2804 , by appropriate control signals 2830 loaded, be provided. For example, the counter 2804 loaded with the value 1,000 to provide 1,000 response slots. The multiplexer 2806 receives serial data coming from the register 2802 on line 2803 and receives error output Q0 on line 2805 , The control logic 2812 provides a selection signal via control signals 2830 to the control multiplexer 2806 to the contents of the shift register 2802 followed by the number of answer slots, depending on the starting number of the counter 2804 to provide. The operation of the multiplexer 2806 thus ensures management 2807 for a signal in a message format to be sent.

The duty cycle modulator 2808 can on control codes of control signals 2830 of control logic 2812 and the signal on line 2807 with supplying a modulated signal TXG on line 2809 reply. Interrupt keying and duty cycle modulation are provided in a manner consistent with the contents of Table 8.

TABLE 8

A transmitted signal XD on line 2425 is from the AND combination of signal TXG on line 2809 (defining a transmission gate) and signal PFSO on line 2423 provided. The signal PFSO defines an unmodulated carrier frequency as given by the CPU 2402 on line 2423 is programmed.

The antenna system 120 can be controlled according to a spatial antenna distribution to support multiple antennas at each of one or more nodes connected by an antenna bus. Each antenna node may be for coupling one or more antennas to the transmitting and / or receiving areas of the monitoring device 124 in a conventional manner. The antennas can be coupled for balanced or unbalanced use when receiving or transmitting. If multiple antennas are used for transmission, the antennas can be controlled with different phases. When multiple antennas are used for receiving, received signals may be delayed for synchronization or provided in a desired phase relationship. Because different antennas of the antenna system 120 Having different radiation (or receive) characteristics, operation of a transmitter having one or more antennas and / or a receiver having one or more antennas provides advantages for communicating with transceivers regardless of transceiver orientation and proximity to other transceivers, as above discussed. The antenna system 120 provides a reconfigurable multi-antenna system with tuning capability for each antenna. In addition to tuning each antenna, the antenna system 120 the ability to disable any antenna used for transmission and to couple the locked antenna to a receiver for immediate reuse as a receive antenna. The antenna system 120 provides multiple transceiver channels in each antenna node with the ability to route signals from one channel to another for signal processing.

The above for the antenna system 120 functions described may be provided by one or more antenna nodes that co-operate on an antenna bus. Special advantages for the system 100 are created by using the in a functional block diagram of 29 achieved described antenna node circuit. The in 29 described antenna node 140 contains CPU 2902 and memory 2904 by data bus 2906 coupled to the program execution. The antenna node 140 also includes an antenna network interface 2908 , an input register 2909 , an output register 2910 , a coupler 2912 , a coupler 2914 , a variety of antennas 150 (including antenna 2916 ) and a variety of transceiver channels 2918 ,

The CPU 2902 receives commands and information and provides a state using data communication on the antenna bus 132 that through antenna network control 2412 with CPU 2402 is coupled. The CPU 2402 the monitoring device 124 returns commands from the CPU 2902 for functions described in Table 9.

TABLE 9

Storage 2904 ensures storage of programs by the CPU 2902 storage of configuration information for other function blocks of the antenna node 140 and in the transceive channels 2918 used tuning parameters. This information may be in the memory 2904 managed in any conventional data storage format.

The antenna network interface 2908 provides data transfer and control under antenna bus 132 , Data bus 2906 and couplers 2914 , The antenna network interface 2908 provides serial / parallel and / or parallel / serial data format conversion for transmitting signals between the serial antenna bus 132 and parallel data bus 2906 , The antenna network interface 2908 can receive signals from the transceiver channels 2918 at receivers 2416 and 2418 the monitoring device 124 buffer. In addition, the antenna network interface can modulate carrier signals from transmitters 2424 and 2426 in the monitoring device 124 receive and buffered signals for the transceiver channels 2918 deliver. The received signals and modulated carrier signals pass between the antenna network interface 2908 and the coupler 2914 on line 2905 ,

The input register 2909 monitors the state of the switch 2907 and shares a switch closure event via data bus 2906 the CPU 2902 With. The desk 2907 can provide any manual data entry function. The desk 2907 is representative of any number of switches, such as toggle switches or a data entry keypad. In a preferred configuration, the switch has 2907 when closed, the CPU 2902 to provide for one or more test and / or measurement functions. Said functions include identifying a test mode at the CPU 2402 the monitoring device 124 via a suitable data communication message via the antenna network interface 2908 one. As the antenna node 140 in a location far from the main computer 122 and / or the monitoring device 124 accommodated and arranged, facilitates a convenient arrangement of a manual switch 2907 for test and / or measuring functions, an installation and maintenance of the system 100 including the installation and maintenance of the antenna system 120 ,

The output register 2910 receives data from the data bus 2906 , stores these data and maintains output signals corresponding to the stored data. From the output register 2910 provided signals guide the operation of the coupler 2912 and the transceiver channels 2918 , Output register signals on line 2910 control the coupler 2012 (eg configuration and matrix switch operations). Lock command signals on line 2912 manage antenna lock functions of the squelch 2920 , Tuning signals on line 2923 conduct tuning functions of the tuner 2922 , Finally, digital signals control on wire 2927 the operation of transceiver channels 2924 (eg, specifying preamplifier gain, automatic gain control and filter transfer functions). Output register signals on lines 2913 . 2921 . 2923 and 2927 are binary digital signals and can work together across multiple transceiver channels 2918 or additional digital signals may be used by the output register 2910 be used for each transceiver channel.

The coupler 2912 may include any conventional circuit for coupling an antenna to an RF channel. For example, the coupler provides 2912 a matrix switch for coupling any antenna of antennas 150 (eg antenna 2916 ) with one or more transceiver channels 2918 , In the same way, any transceiving channel, for example 2924 , with one or more antennas 150 over the coupler 2912 be coupled. The coupler 2912 provides bi-directional coupling for both received and transmitted signals and supports multiple received and transmitted signals simultaneously. The coupler 2912 may also be suitable for switching to select antenna elements of an individual antenna 2916 of antennas 150 to care. For example, one or more of conduits may be 2911 and 2915 with one or more wires 2925 and 2935 coupled to implement: (a) phased transmit or receive; (b) using antennas (or elements) in sequence; (c) scanning while interrogating or transmitting data; or (d) provide working energy to antenna (s) that are different / different from the antenna (s) used for polling or for data transfer. The coupler 2912 couples antenna elements (eg antenna 2916 ) for use with one or more transceiver channels 2918 according to the output register 2910 received signals on line 2913 , An antenna element selection discussed above may be for any one or more antennas of the antennas 150 be performed.

The coupler 2914 For example, any conventional RF switching system may couple and buffer modulated carrier signals and received signals between antenna network interfaces 2908 and one or more transceiver channels 2918 contain. If, for example, the antenna bus 132 provides a modulated carrier signal for transmission, the antenna network interface 2908 the modulated carrier on the signal line 2905 to the coupler 2914 deliver. The coupler 2914 The modulated carrier signal can be transmitted via one or more signals TRI1 2951 until TRIN 2955 with one or more transceiver channels 2918 couple. In addition, the coupler 2914 buffer any received signal (e.g., TRI1 to TRIN) to receive one or more feedback signals TRC1 2953 TRCN 2957 provide. The signals TRC1 to TRCN of coupler 2914 leave a first transceiver channel 2924 provide an output signal TRI1, for example in accordance with: (a) from the coupler 2912 received antenna signals 2925 , and (b) via any one or more other transceiver channels 2918 , for example RF channel 2934 , received signals. The coupler 2914 thus provides for the combination of received signals from one or more RF channels on the signal line 2905 to the antenna network interface 2908 to be delivered. The coupler 2914 allows a single RF channel (e.g. 2924 ), a channel signal (eg 2925 ) to a signal from one or more other RF channels (eg, TRC1 ... TRCN) and the resulting received signal (eg, TRI1) on line 2905 to the antenna network interface 2908 to deliver.

The transceiver channels 2918 include one or more parallel circuits for performing, inter alia, antenna tuning and disabling functions. Each transceiver channel is a functional equivalent of other transceiver channels to provide similar (but configurable) functions on each of multiple channels. Each transceiver channel includes an RF channel circuit, a tuner, and a trap circuit.

The RF channel circuit 2924 can provide transmit signal buffering and receive signal filtering and amplification in a conventional manner. Special advantages are in the system 100 using the RF channel circuit 2924 from 30 achieved. The RF channel 2924 from 30 contains an amplifier 3002 , an analog switch 3004 , Filters 3006 , a programmable preamplifier 3008 , a differential amplifier 3010 and an analog switch 3012 , For one on an antenna 150 modulated carrier signal to be transmitted receives the RF channel circuit 2924 a signal TRI on line 2929 , it provides buffering and amplification through the amplifier 3002 and passes the buffered signal through the analog switch 3004 as signal TRA on line 2925 to the coupler 2912 , For one of the coupler 2912 received signal, the signal TRA occurs on line 2925 via the analog switch 3004 to filter 3006 , The filters 3006 provide some conventional filtering function (e.g., lowpass, bandpass, notch, and highpass analog or digital filtering). If the received signal TRA contains an OOK modulation, the filters may 3006 Include time domain signal processing functions, for example Schmitt trigger and / or edge enhancement functions. The programmable preamp 3008 responds to control signals 2927 from the output register 2910 by providing a transfer function with programmable gain on numerous frequencies (eg, automatic gain control).

The differential amplifier 3010 receives the output signal from the preamplifier 3008 and can a signal TRC1 on line 2953 via the analog switch 3012 receive. The analog switch 3012 is from the output register 2910 via signals 2927 controlled. If the analog switch 3012 passing the signal TRC1 to the differential amplifier 3010 allowed, the differential amplifier can 3010 a Perform analog subtraction to a difference signal TRI1 on line 2951 provide. The analog subtraction may provide additional common mode rejection or may provide an improved signal for receiving a response from a transceiver 201 if, for example, more than one antenna 150 is used for receiving the response signal. The differential amplifier 3010 For example, programmable phase shift circuits may be used to enhance common mode discarding or signal boosting under the direction of signals from the output register 2910 contain. Phase correction may be desired when antennas with different configurations or different orientations send signals to the differential amplifier 3010 deliver.

The tuner 2922 Fits the impedance of an antenna (eg antenna 2916 ) to an RF channel circuit 2924 at. The effects of the coupler 2912 and that of the coupler 2912 performed antenna element selection is by the operation of the tuner 2922 Taken into account. The tuner 2922 may include any conventional tuning circuit. The tuner 2922 preferably includes impedance matching elements connected between an RF channel circuit and an antenna in response to signals from the output register 2910 optionally introduced. The memory 2904 may provide data and methods for determining suitable control signals for the tuner 2922 contain.

The memory 2904 (or memory 2404 , or memory in the host 122 ) contains a field with values for the output register 2910 wherein each value is a bit for controlling the closing of each of a plurality of switches in the tuner 2922 contains. The field is indexed by an integer that matches a desired operating frequency (eg, a bin number discussed above). Values for said field may be determined according to an antenna test method. An antenna test method may include the steps of: (a) instructing a transceiver channel (eg, including tuner 2922 ), which is used both for sending (eg from sender 2424 ) of a test signal as well as for receiving (eg using the receiver 2416 ), the test signal having a suitable amplitude and test frequency throughout the test procedure; (b) instructing the use of a narrow band detector (eg synchronous detector 2506 from 27 ); (c) selecting and directing a switch closure combination and observing a detector output; (d) comparing the detector output with a maximum observed detector output; (e) when the detector output exceeds the maximum detector output, updating the maximum observed detector output to coincide with the detector output and noting the switch closure combination consistent with the detector output; (f) repeating steps (c) through (e) until all switch combinations have been selected; (g) storing the switch closure combination matching the maximum detector output in a field for the antenna under test (or combination of antennas) indexed by the test frequency. After testing each installed antenna (separately or in combination (s) with other installed antennas) at one or more test frequencies, the results of several tests can be stored in an integrated field having a recommended antenna (or combination of antennas) for each frequency a recommended tuner switch combination contains. The integrated field may be in volatile or non-volatile memory in the host computer 122 , Storage 2404 or memory 2904 get saved.

Special advantages are in the system 100 by using the tuner circuit 2922 from 31 achieved. The tuner circuit 2922 from 31 contains one or more shunt circuits 3100 , the signal lines 2925 bridge that through the tuner 2922 between the RF channel circuit 2924 and the coupler 2912 to step. Each shunt circuit includes an analog switch and a capacitor, respectively. For example, the analog switch 3102 from an output signal from the output register 2910 controlled. When closed, the analogue switch closes 3101 the capacitor C3102 via the lines 2925 to increase the capacitive load. In the same way, the analog switch 3103 connect the capacitor C3104; and can the analog switch 3129 connect the capacitor C3130. Capacitors C3102, C3104, and C3130 may have values in a binary sequence, for example, as commonly used in a digital-to-analog converter circuit.

The memory 2904 may be a method for operating a squelch 2920 to perform a suitable blocking function, as discussed above. The antenna network interface 2908 may provide a mechanism for analyzing the phase of a signal to be transmitted and such phase information on the data bus 2906 to the CPU 2902 deliver. The phase information may be indicated by a suitable interrupt corresponding to a zero crossing. From the output register 2910 provided lock command signals on lines 2921 can via the output register 2910 according to the phase information discussed above, when the signal processing latency of the CPU 2902 (eg, interrupt latency) does not provide a lock command signal in reliable close proximity to a zero crossing of a modulated carrier signal to be transmitted. The CPU 2902 can send a command signal to the output register 2910 deliver the variations of RF channels 2918 and accommodates variations of the modulated carrier signals for squelch 2920 to operate in an efficient manner. It is believed that the blocking function is efficient when power is rapidly consumed on antenna elements in close proximity to a zero crossing of the phase of a signal to be transmitted. The lockout function should be used in all related circuits, including distributed capacitances of, for example, couplers 2912 , Tuner 2922 and RF channel 2924 to take account of stored energy.

The blocking circuit 2920 may include any conventional blocking circuit. Special advantages are in the system 100 by using the squelch 2920 from 32 scored the inverters 3201 , Gated Source Positive (GSP) 3202 , Filtered Rectifier Positive (FRP) 3204 , Gated Source Negative (GSN) 3206 , Filtered Rectifier Negative (FRN) 3208 , FRP 3244 , GSP 3244 , FRN 3248 and GSN 3246 contains.

GSP 3202 includes a switching transistor Q3210 with a base connected to an analog switch 3212 and an analog switch 3214 connected is. The collector of the transistor Q3210 is with FRP 3204 coupled. In operation, signal SQ * controls the analog switch 3214 for coupling a -9 volt supply through resistor R3216 to sink current from the base of transistor Q3210 which turns on transistor Q3210 and supplies current from a +5 V source at the emitter of transistor Q3210 via the collector to FRP 3204 supplies. In the opposite phase, the signal SQ controls the analog switch 3212 to couple a +9 V source to the base of transistor Q3210, which quickly turns off transistor Q3210. GSN 3206 has an analog structure for opposite polarity operation for transistor Q3211.

FRP 3204 contains a series filter consisting of resistor R3230 and the parallel combination of resistor R3232 and capacitor C3234. The output of the series filter feeds a node between a pair of diodes D3236 and D3238. Diode D3238 is forward biased by the current supplied through resistor R3230 and resistor R3232. The diode 3236 sticks branch 3282 the signals 2925 with a voltage that is a diode drop across ground; the diode drop is supplied by diode D3238. FRN 3208 has an identical structure as FRP 3204 on, except that the diodes 3237 and 3239 have reverse polarity orientation. In operation, the squelch is stuck 2920 from 32 the branches 3281 and 3282 alternatively with plus and minus current sources for quickly extinguishing any potential difference between branches 3281 and 3282 , In operation, an antenna may be disabled using the circuit 2920 from 32 in a manner sufficient for use with a receiver in less than one and a half cycles of a transmitted carrier signal (e.g., about 35 μs).

The antenna bus 132 can be any serial or parallel bus for controlling the antenna system 120 through the monitoring device 124 be. The antenna system 120 may be organized as a bus, a chain, a star, or a hierarchical combination of subnetworks. Special advantages are in the system 100 by using an antenna bus 132 achieved with four differential signals spatially as one of the monitoring device 124 controlled network are arranged. For example, the antenna network interface contains 2908 from 33 Interface buffer 3302 . 3304 . 3314 and 3316 , Signal selector 3306 , Shift register 3308 , Send buffer 3310 , Receive buffer 3312 , Shift register 3320 , Output multiplexer 3322 and control registers 3324 , The antenna bus 132 contains any suitable number of the signals described in Table 10.

TABLE 10

When signals TC and RC are asserted, data communication in series on lines TD and RD provides information flow between CPU 2902 and CPU 2402 the monitoring device 124 , When no signals TC and RC are asserted, the signals TD and RD respectively provide transmit and receive signals from one or more transceiver channels to one or more transmitters or receivers in the monitor 124 , The antenna bus 132 uses differential line drivers for all signals so that antenna nodes are at a considerable distance from each other for convenient antenna placement 150 and 152 spatially distributed. The monitoring device 124 delivers (via antenna network control 2412 ) Signals TC, TD and RC to all antenna node interfaces 2908 the respective antenna node 140 . 142 simultaneously. Data communication over signals TC, TD and RC may include any conventional protocol for coordinating non-disjoint use of each shared signal line (e.g., lines for signals RD). For example, the signal TD may include a command followed by an address. Every CPU 2902 can get the received address from the shift register 3308 compare with a predetermined address to the line driver 3316 via a tax register 3324 at a time determined by the protocol and the result of the address comparison to enable data communication with the monitoring device 124 without interference from other antenna network interfaces in other antenna nodes.

The control of the antenna node 140 through the monitoring device 124 can be achieved using any conventional instruction set and command syntax, for example the instructions discussed above with reference to Table 9.

antennas 150 may include one or more antennas having numerous geometries for the detection of response signals from one or more transceivers of the system 100 contain. Planar antennas can be used in a variety of configurations. For example, in the 34 and 35 defined antennas for particular advantages in the system 100 , These planar antennas may be from one or more antenna nodes 140 . 142 be supported in any desired convenient combination. A passage 3500 contains walls 3506 and 3507 , Top 3504 and above the base level 3501 arranged base 3505 , Although not drawn to scale, the passage points 3500 Preferably, a square aspect ratio for the opening through which objects can pass. It's out been found that the passage 3500 provides adequate performance when constructed as a passageway for personnel (including parts of a building, eg, floor, wall or ceiling of a corridor) and when used as a passageway for porters of objects (with an opening of approximately three feet square, ie about one square meter). Smaller passages can be used for table instruments.

A reference coordinate system with an origin 3510 serves to define the plane of each planar antenna. Angle Alpha (α) is measured in the XY plane from the X axis. Angle Beta (β) is measured in the XZ plane from the X axis. Angle gamma (γ) is measured in the YZ plane from the Y axis.

For practical reasons, an antenna with more than one winding can not exist in one plane. In the 34 However, planar antennas as described may be made to approximate the antenna pattern characteristic produced by a theoretical planar antenna. Alternatively, antennas may be formed with similar planar angles along an axis perpendicular to the plane (eg, helical) or loops therealong.

An antenna 3401 is in the plane defined by points A, B, C, D, that is, in a plane parallel to the XZ plane at the opening of the passage furthest on the Y-axis from the origin 3510 constructed away. The antenna 3402 is parallel to the antenna 3401 but still closer to the origin 3510 , Movement of a transceiver along an axis through the passage parallel to the y-axis may be accomplished by examining the time when the peak response signal strength from each of the antennas 3401 and 3402 will be determined. The antenna 3403 is in turn parallel to the XZ plane and also exists at the midpoint of the pass (eg, each point J, K, L exists at the midpoint of a segment NB, OC, PD parallel to the Y axis). The antenna 3404 can be arranged at an angle α = 45 ° when the passage 3500 is essentially cubic in geometry. Similarly, the antenna 3405 perpendicular to the antenna 3404 run when the passage 3500 is essentially cubic. The antenna 3406 is oriented in a plane with angles α = 135 ° and γ = 135 °, and is of the type described in the cited related patent application S / N 09 / 233,755. The antenna 3407 has an orientation complementary to the antenna 3406 on. The antenna 3408 lies in a plane parallel to the ground plane 3501 , The antenna 3409 and antenna 3410 run parallel to the YZ plane and can be in respective pages 3506 and 3507 be constructed.

Transceive channel circuit, in particular squelch 2920 should be located for optimal performance (minimum generation of out-of-band noise) as specified in the table. The points T, U and V halve segments LK, HG and DC, respectively. Halve points S segment PK.

A passage with antennas 3402 . 3403 . 3406 . 3407 . 3408 and 3409 is preferred for an object identification system in which objects 102 to 112 through the passage for identification and data transfer. Other combinations of the antenna orientations discussed above may be used for economy, reliability, or enhancement of certain system performance.

Every antenna of the antennas 150 can be constructed from multiple loops as a planar antenna. Special advantages are in the system 100 by using an antenna from in 36 achieved type described. The antenna 3600 contains three loops and connectors 3601 . 3602 . 3603 that are based on a common connection 3611 Respectively. The loops may be formed of any conductor, including a shielded conductor for limiting E-field radiation while transmitting or receiving magnetic field radiation. In addition, the antenna contains 2916 a Q modifier circuit 3604 , The Q modifier circuit 3604 contains diode D3612, diode D3614 and resistor R3616, all from terminal 3610 until connection 3611 connected in parallel. In operation, a transmission signal, for example, signal TRA on line 2925 via coupler 2912 to be imposed over two connections: a first one consisting of the set of connectors 3601 . 3602 and 3603 is selected, and a second one selected from the sentence consisting of 3610 and 3611 consists. If the connection 3610 is used, a transmit signal of suitable magnitude may bias diode D3612 and D3614 forwardly to shunt resistor R3616. This results in a relatively high Q antenna circuit. On the other hand, one from the antenna becomes 2916 received signal having a signal magnitude insufficient to forward bias diodes D3612 and D3614 through resistor R3616. It will result in a relatively low Q antenna circuit. A low Q antenna is typically characterized by a broader bandwidth sensitivity than a higher Q antenna. When transmitting energy to drive one or more transceivers, a higher Q antenna is preferred.

If objects 102 to 112 to interrogate while making a passage from the above with reference to 35 can pass through query and data communication reliability by arranging objects 102 to 112 be improved in one or more carriers. A transport carrier may include one or more resonant antenna circuits for focusing transmitted and received energy. carrier 3700 from 37 Figure 4 illustrates an example of a structure in which objects of the type described above may be arranged for convenient interrogation and data communication. A carrier of any geometry may be used to extend or design the antenna sensitivity characteristic of the antenna of an object, for example, an antenna 202 from object 104 from 2 , be used. For example, the transport carrier contains 3700 side walls 3702 and 3704 and base 3706 , In addition, the carrier contains 3700 an antenna circuit 3708 with a loop conductor and series capacitor C3710. The antenna circuit 3708 has, due to the value of the capacitor C3710, a resonant frequency selected to transmit energy and / or communication between the monitoring device to an object 124 and to improve an object. In a preferred configuration, the antenna circuit is 3708 is constructed with a relatively low Q and a resonant frequency that is substantially different from frequencies that can be used for interrogation and data communication. When the monitoring device 124 a scan signal or subscan signal, with reference to FIG 4 The type discussed with the antenna circuit can be used 3708 connected call signal, as discussed above, are easily identified, so that a query on the resonant frequency antenna 3708 can be avoided.

The carrier 3700 may be a second antenna circuit 3716 included in a similar way as antenna circuit 3708 constructed with a series capacity C3714. The antenna circuits 3708 and 3716 may be coupled in any conventional manner (eg, toothed loops, overlapping regions) that places a portion of each loop in close proximity for magnetic field coupling or electric field coupling.

As discussed above For example, the memory may contain some device for data storage (e.g. As semiconductor circuits, circuits of discrete components and magnetic and / or optical media).

The previous description discussed preferred embodiments of the present invention, which are modified or modified can, without being outside the scope of the present invention in the claims, to get. While for the sake of clarity, several more specific embodiments the invention have been described, the scope of the Invention be dimensioned by the following claims.

Claims (14)

Antenna network ( 120 ) for operation with a provided control device ( 124 ), wherein the controller provides a first signal for transmission through the network, responds to a second signal provided by the network in accordance with receipt by the network and provides a plurality of binary coded instructions to the network, the network comprising a plurality of Antenna node ( 140 . 142 in which: a) each node is coupled to the controller for receiving a respective one of the plurality; and b) each node comprises: (1) a plurality of transceiver channels, each channel ( 2918 ): (a) a transmission circuit ( 3002 ) for transmission in response to the first signal; (b) a squelch ( 2920 ); and (c) a receiving circuit ( 2924 ), wherein the second signal is selectively provided in response to an output signal of the receiving circuit; and (2) a coupling device ( 2912 ) for selectively coupling a particular transceiver channel of the plurality to any one of a plurality of provided antennas ( 150 ) in accordance with the respective command. Antenna network according to Claim 1, characterized in that each antenna is provided with a respective squelch at a position ( 3401 , V) of the antenna, which provides for electrical symmetry with respect to a respective reference ground plane, is selectively coupled. Antenna network according to claim 1, characterized in that a squelch of the plurality of a power source ( 3202 . 3206 ) for each branch of the respective intended mute antenna has. Antenna network according to Claim 1, characterized in that the network comprises a plurality of network nodes ( 140 . 142 ) having. An antenna network according to claim 1, characterized in that: a) a first node of the network also receives a third signal provided by a second node of the network; and b) the transceiver channel of the first node further comprises a differential amplifier ( 3010 ) responsive to a respective receive circuit output signal and the third signal, the second signal being provided in further response to an output signal of the differential circuit. Antenna network according to Claim 1, characterized in that: a) a specific network node has a memory ( 2904 ) having; and b) a transceiver channel of the particular network node further comprising a tuner coupled to the memory for tuning the antenna in accordance with contents of the memory ( 2922 ) for operation with at least one of the transmitting circuit and the receiving circuit. Antenna network according to Claim 6, characterized that the Memory on a given command of the variety of binary coded Commands to modify the memory contents responds. Antenna network according to Claim 7, characterized that the Memory contents in accordance with a working frequency for the antenna network are indexed. Antenna network according to Claim 1, characterized in that the control device is connected to a particular network node of the plurality by a conductor ( 132 ), which transmits indexes of a command at a first time and indexes of the first signal at a second time. Antenna network according to Claim 1, characterized that at least a knot as well a switch which sends a signal to the control device provides when the switch is operated by a user, to coordinate the operation of the controller with activities by the user. Antenna network according to Claim 1, characterized that: a) each command is delivered to the network with an address; and b) every node as well a comparator for comparing the address with a respective one has a predetermined address to respond to the command, if the comparison is successful. Antenna network according to Claim 1, characterized that at least a knot as well a bandwidth circuit coupled to the antenna for providing the antenna in at least one of a first working mode with a first Q and a second working mode with a second Q has. Antenna network according to Claim 12, characterized that the Bandwidth circuit is in series with the antenna. Antenna network according to Claim 12, characterized that the Bandwidth circuit has in parallel: a) a resistor; b) a first diode parallel to the resistor; and c) one too the second diode parallel second diode, wherein the second diode is oriented with respect to the first diode with polarity reversal.